Shin Megami Tensei 4

[SnowFire]

Shin Megami Tensei 4 is a 3DS RPG that wrangles with the deep moral issues of our time, such as "would releasing human-eating demons across the land be a good idea?" and "If a creepy little girl with a distorted voice asks you to revive her, should you?"  Well, the game's name means "Resurrection of the Goddess", so what's the worst that could happen, anyway…?


Mechanics info first.

Initiative:  Initiative is determined Dragon Warrior 1 style.  Flynn's Agility is compared to the highest agility on the opposing side (I believe?), and there's a roughly 50/50 chance assuming equal Agility.  Whoever wins has their entire team go first, after which there is strict alternation between "sides".  As such, in the long-term, everything in SMT4 has perfectly average speed.  Agility only matters for the first round's initiative, which is still extremely important in-game.  The effect is fairly subtle unless there's a large difference - e.g. a 180 Agility Flynn should go first ~95% of the time vs. 80 Agility enemies, while a 40 Agility Flynn might only go first 65% of the time vs. 25 Agility enemies.

Turns: Like other SMT games, SMT4 follows the Matthew 25:29 school of design:  For to all those who hit a weakness, more will be given, and they will have an abundance; but from those who miss, even what little they have will be taken away.

Turns are allocated "per side"; PC characters and regular enemies usually generate 1 turn for their side, so if everything goes boringly, each character takes an action per round.  Bosses generate more turns, usually 2-3.

• If a character hits a weakness or makes a critical hit, an extra half-turn is granted to their side.
• If a character misses, or has their attack nulled (by elemental nulling), a turn is removed from their side.  For status ailment and instant death attacks, a turn is lost only if the effect is nulled, not if it merely misses.  If their attack is reflected or absorbed, ALL turns are lost.
• If both of the above happen at once - say, a double-hit attack that both gets a critical hit and a miss - a turn is removed from their side.
  
• Repeats of the above effects within a single action won't gain or lose more half-turns.  (An MT attack that hits weakness 3 times only generates 1 half-turn.) 
  
• If you'd lose a turn when you have no turns to lose - say, the end of the round - nothing happens (the turn loss doesn't carry over to the next round).
  

Half-turns are exactly like normal turns, except you can't get more half-turns off of them.  They are also intelligently "spent first" if an attack is made that wouldn't generate a half-turn.  Example: a boss has 3 turns.  She gets a critical hit in her first attack, and has 2 turns and 1 half-turn.  She makes another attack that is not a critical.  Now she has 2 turns (the half-turn was spent).  She makes a 3rd attack and that is a critical - she's now at 1 & 1.  She makes a 4th attack, which is a critical, so she now has 2 half turns (the normal turn is spent in this case).

Defense / Magic Defense: There is none in this game.  Everything is exclusively based off HP, Agility (for dodge chance), elemental resistances, and very rare Pierce attacks that ignore said elemental resistances.

Evasion: Based off Agility and in general not common without -kaja/-kunda effects.  I suspect that if two people of equal Agility attack each other, the hit rate is 100%, and only an Agility edge starts creating dodge chances.

Critical hits: Critical hits offer +50% damage and an extra half-turn, as noted above.  They are based off the Attacker's Luck.  Critical hits can happen on any damage-causing move.

Elements:

• Physical and Gun both run off Strength & Dexterity.  Regular physicals favors Strength, regular gun shoot / gun skills / physical skills (!)  favor Dexterity.  (To be clear, increasing Strength still buffs Guns / skills, just not as much, and increasing Dex buffs regular physicals, just not as much).
• Fire, Ice, Force (=Wind), and Lightning run off Magic.
• Almighty also runs off Magic (with one or two exceptions).  Nothing in the game resists Almighty, and Almighty pierces Reflect effects (Makarakarn). 
• Light and Dark are exclusively % chance of instant-death effects (ID).  Odds are allegedly influenced by both caster & victim Luck, but if so, the effect is subtle.
• Status isn't an element, but pure status effects have their own symbol, and also pierce Reflect magic.  Possibly also based on caster / victim Luck, but with small effect.

As an interp note, lots of Gun attacks are not flavored as being Gun-based in-game (e.g. a demon Porcupine with "Needle Shot" or an archer with "Myriad Arrows", and Flynn can use Gun-elemental before finding an actual Gun), so Gun should really be seen as "Ranged" and include Bows & the like.  Light & Dark nulling should be treated as ID immunity and not nulling other game's damaging Holy/Dark spells, which are classed as Almighty in SMT4 (Megido, Holy Wrath, Sea of Chaos, etc.).  Finally, while Earth is not an element, Earth elementals get Lightning buff skills, and there appears to be a Force / Lightning rivalry which might be interpreted as the Wind / Earth rivalry.  Your call if this means anything.

Resistance levels are weak, neutral, resist, null, reflect, & absorb.  Absorb gains life equal to the damage done; reflect reflects the damage back in unstoppable, unreflectable, unresistable form; nulling causes attacks to do 0 damage; resist causes attacks to do half damage; and weakness grants a +50% damage boost.  In addition to these, see above section on "Turns"; null/reflect/absorb eat a turn, hitting a weak point for massive damage grants a half-turn where the hapless opponent can be smacked again.

Status effects: SMT4 has one positive status effect and several fairly inconsequential negative ones.  The negative ones can wear off immediately, and in fact it is common to have "0 turn" durations on the turn-skippy ones.  (They are still fine as conditional turn-skip attached to damage in-game, but trashy in a duel as a result due to falling off immediately half the time and doing nothing.)

• Smirk: See Matthew quote above, more the rich get richer.  If a weakness is hit / a critical hit scored / an attack that gets nulled / reflected / absorbed is used against a character... the affected character has a ~40% chance of entering Smirk status.  Smirk lasts until the character's next action and grants +60% damage, auto-hits, & a very high critical hit rate.  Defensively, the character's weaknesses are canceled and they get ~85% evasion (doesn't apply to pure status effects).  Smirk is canceled (and prevented) by any status ailment.  Yes, enemies get smirk too, this is the source of massive boss killing sprees of crit -> Smirk -> 100% hit rate MT doom damage.
• Poison: 1/8 max HP damage per turn.  Doesn't wear off.
• Sick: -25% damage done.  Doesn't wear off, has a 5% chance per action of spreading to someone new on the same side.
• Panic / Confusion: ~30% rate of turn skip, ~20% rate of random action, ~50% rate of no effect.  Random actions aren't traitorous ones (e.g. paniced characters never attack allies or heal foes).  ~40% rate of wearing off per turn.
• Sleep:  Takes an additional 25% damage + 100% turn skip.  ~60% rate of wearing off per turn.
• Bind / Paralysis: 100% turn skip.  ~40% rate of wearing off per turn.

Buffs and debuffs: Attack, Defense, & [Hit / Evasion] can be buffed & debuffed to a maximum of +3 and a minimum of -3.  Buffs last until end of battle (unless dispelled).  In general, almost all buffs adjust their targets by 1 level.  Taru-/Raku-/Suku- kaja all give +1, -runda gives -1, Fog Breath / War Cry / Acid Breath all debuff 2 categories -1 each, Debilitate debuffs all 3 categories -1, Luster Candy buffs all categories by 1.
* Attack buffing & defense debuffing is by 20% intervals.  0 to 3 would thus be /100%/120%/140%/160% damage.  This stacks, so +3 Attack vs. -3 Def = 1.6*1.6 = 256% damage.  It doesn't seem quite as harsh for attack debuffing / defense buffing; I believe that it's a 15% interval there (so Atk -2 = 30% less damage, Atk -2 vs. +1 Def = .7 * .85 = 59% damage).
* Hit / Evasion is harder to measure, because I don't know the evasion mechanics.  The effect is fairly subtle, yet noticeable in-game because multi-hit MT is common and a single miss in such a case is ruinous.  I would guesstimate that each level is approximately +8% to hit and +8% evasion.  An enemy with -3 Hit/Evasion and a default 105% hit rate vs. a team with +3 Hit/Evasion will see the PC team always hit and the PCs dodge around ~45% of the time.  These are vague impressions, not backed by rigorous testing.
* A few rare effects "set" the buff level.  An effect that "sets Flynn to -3 Def" doesn't move +2 to -1, it just goes directly to -3.

[SnowFire]

I have a strong preference for humans, former humans, and demons that have the good sense to dress up as humans and interact in the plot, so that's all that's here.  Unfortunately, the plottiest bosses are all splitpath.  Sigh.

Also blah blah blah SPOILERS blah blah cleanse the heretics who have rejected God's holy order blah blah.

All bosses:

• Are immune to Talk recruitment.
• Can get "Smirk" status just as PCs or regular enemies can, and often have extra turns to farm them with, so crits -> Smirk -> more crits can turn into a killing spree.
• Are fought by 4 PCs + guests, and backrow characters can be swapped in.  While there are technically 3 different guests, only 1 will be active per round, and if that guest takes lethal damage the other guests won't sub in and the guest slot will stay vacant until the end of the battle.  Thus there are 5 PCs worth of offense to throw every round + whatever penalty you want to impose for being able to cheaply swap in reinforcements.
• Their multitarget (MT) abilities will NOT hit guests.  Their single target (ST) abilities can and will.
• Unfocused abilities (e.g. Shalt Not Resist) can't be specifically targeted, for team battles.  (There are PC versions of many of these as well, they just randomly hit the other team.)
• Plot-heavy bosses have conversation triggers based on HP.  These usually happen as soon as the HP is hit - i.e. in the middle of the PC round, usually.  There are a few exceptions when the boss might gain / lose actions, and thus the trigger is delayed to the start of their round.  I'm the type of person who enjoys trying to figure out how other duelers would respond, but if you're not, the effects are usually subtle enough to not care too much, especially if you always assume the opponent always "picks correctly."
• Boss Agility isn't even guesstimated (you can only see enemy stats if you've defeated them once, thus the real values can only be seen in a New Game+).  My Flynn was Magic & Agility focused, which makes most bosses "slow."  An all-stats-equal Flynn build would see most bosses at roughly equivalent or slightly higher Agility, I suspect.  (Or who knows, maybe all the lategame bosses always go last, and I didn't notice because my Agility was so high as to go first naturally anyway.)

PC damage averages will be "naive" averages that pretend crits or buffs never happen, and that you don't have low-damage demons just pass their turn to Flynn.  As such, especially for the later bosses, you probably shouldn't actually use this value straight-up, although I've provided it as a balance.  Naive boss PCHP values are via assuming each round of total player offense ignoring resistances and half-turns = .4 PCHP.
(Boss HP) / (average PC damage * 4 + guest damage) * .40. 
Adjust this as you see fit.  For example, a boss who could survive 3 rounds of pure offense would have 1.2 PCHP (but if said boss had an ice-weakness, then they'd be effectively 1-rounded in-game if you deploy 4 demons with ice attacks).  Some of the later bosses I've also included some rough w/ buffs guesstimates that assume the first round is spent buffing up for 180% damage afterward in the fight.

PC HP averages assume that the 4 characters are Flynn, an HP-optimized demon, a balanced demon, and an MP-optimized demon of appropriate level.  As above, buffs can mess with the real durability in-game.  One is of special note: the spell Doping.  It increases the max HP of all active PCs by 30% (but doesn't provide any healing and doesn't affect PCs in the stock).  It's not a very common ability, but it is very good if the team can just use it on turn 1-> healing.  Your call on how much to hold this against bosses.  (Thankfully not as huge a split as FF12 bosses & Bubble, which *doubled* your max HP in that game…)

All stats are from "Normal" = Prentice difficulty level.  (Game is mistranslated, manual & plot would think that "Fellow" > "Prentice", but no, Fellow is ez mode, Prentice is normal.)

--

PC HP: 140
PC damage: 70.  Guest damage: 60


Issachar
Biblio-Corrupted Rebel Necroid
"...remember...  when... I was providing all the expository dialogue...  because you couldn't speak?  ...those were...  good times..."

Type: Undead
Resists Light / Darkness
HP: 564 (.66 PCHP)
AGL: 22 (vs. 40 for AGL-twinked Flynn), went first 2/5 times

2 actions per round

Attack: 45 damage, ~90% accuracy
Bouncing Claw: 1-3 hits to a single target of 45 damage per hit.  Average 90.
Critical Wave: MT low accuracy / high crit attack, high variance.  60 damage when it doesn't crit.  Went 11/22 in accuracy (50%), which is high because some of that was post-Fog Breath, so call it more like 40% accuracy.
Fog Breath: Debuff Attack & Hit / Evasion -1, MT

Conversation triggers:
50% HP + start of Issachar's turn: (Basically) "Are you a noble or a commoner." 
"I'm a Casualry" (Commoner) - Issachar skips his entire turn.
"I'm a Luxoror" (Noble) - Issachar gets 2 extra actions.
Ignore - Nothing happens.
25% HP: A "please kill me" question with no in-battle consequence, but it triggers instantly at this threshold.  If this question has already happened, the above question doesn't.  (e.g. 40% damage round 1 -> another 40% damage round 2 -> "finish me off" -> no noble / commoner question asked at the start of hte round)

(For what is going on here, Issachar has been brainwashed by "literature" to hate nobles.  Don't let the commoners read the mystic runes of Japanese, people, they get ideas.)

--
Somehow High Light despite having a turn 1 OHKO in theory, WTF.  Issachar is easily 2-rounded in-game such that you never see him take a single action due to triggering his question immediately (at least if you went first).  If you don't quite trigger the question turn 1, he likes to use Critical Wave which misses a lot and tends to be his only action (unless he got lucky with it, and then he might just wipe the party on the spot off the extra actions, SMT balance), his regular attack can miss, he's a mess.

In the DL, if he gets a turn, he can unload with 2x Bouncing Claw for ~1.28 PCHP damage on average with huge variance, and god forbid he runs into a naive / overly honest noble who can't one-round him…  but if his opponent can deal between .33-.50 PCHP damage per round and have the good sense to at least lie, he's done.

--


PC Level: 51 for Flynn, 47-49 for relevant demons
PC HP: 465 (w/ Doping: 600)
PC MP: 210
PC Damage: ~260 ignoring resistances.  Guest offers ~100 ignoring resistances.


Yuriko aka Lilith
Gnosis Granting Shadow Samurai
"You, girl...  It's a shame you won't ever find out how your manga ends.  After your last volume....  Oscar finally reunites one evening with her childhood friend and..."

HP: 7000 (~2.40 PCHP)
Type: Night
Weak to Gun
Resists Force, Ice, Fire
Absorbs Lightning
Nulls Light, Dark
Went first 0/6 times

Very accurate, will sometimes dodge (~5% rate).  Notable critical hit rate (~15%?) which gets better under Smirk, as usual, she probably has high Luck.

3 actions a turn

Attack - 105 physical damage
Silent Prayer - Resets all buffs / debuffs, field.  (Does not affect status or max HP increases.)
Maziodyne - 180 MT Lightning damage
Dream Needle - 200 ST Gun damage, ~70% chance of Sleep
Spirit Drain - 45 MP damage.  Won't use until at <50% health.
Megidola - 210 MT Almighty damage.  Won''t use until at <25% health.

Conversation Triggers:
75% Health: "Let me see that hatred in your face.  Let it heat your blows." 
Glare: Yuriko gets +1 Atk / Hit
Smile: Yuriko gets -1 Def
Ignore: Nothing happens.
50% Health: "You feel it, don't you?  The thrill of combat... The rush of power that surges from within..." 
Agree: Flynn gets -1 Atk / Def / Hit
Disagree: Yuriko gets (another) -1 Def
Ignore: Nothing happens
25% Health: Blah blah blah knowledge & wisdom is awesome, you're just slaves of God, etc.  No effect other than unlocking Megidola spam.

--
Godlike.  Duh.  Even when she's not triggering crits and her target is sleep immune, 3x Dream Needles are going to leave a mark (1.29 PCHP!), and 3x Maziodynes are almost as good (1.16 PCHP).  Unlocking Spirit Drain is bad for her in-game - ST waste-a-turn - but might have occasional weird merit in the DL.  Meanwhile she mocks elemental magic.

Unfortunately she is splitpathy, as boss Yuriko is Jonathan-path only.  Walter-path gets her as a PC you can fuse instead, but blargh to PC demons in the DL.

--

Level: 63 for Flynn, 59-62 for demons
PC HP: 580 (w/ Doping: 750)
PC damage: ~280 ignoring resistances/ crits.  Guest damage: 200


Kenji
Infernal Traitor King
"...remember when I backstabbed you in an alternate dimension's backstory and killed you?  ...No?  That's understandable, I guess…"
Type: King
HP: 8000 (~2.40 PCHP.  Including buffs & debuffs: 1.70 PCHP or so?)
Weak to Fire & Force... sort of.
Nulls Light & Dark
Rather than take +50% damage from Kenji's weaknesses (Fire & Force), he instead takes -33% damage.  (e.g. an attack that did 100 Fire damage would, rather than 150 damage, inflict 67 damage.)  PCs still get the extra turn and potential Smirk status, so it can still be worth it.
Fairly low critical rate (5% or so?  Still comes up because triple-acting + some actions get 4-8 hits)
Went first 0/6 times

3 actions a turn

Tarukaja: Buff Attack +1, MT
Attack: 125 physical damage, MT
Conqueror Spirit: 2x physical hits of 140 damage, MT (280 damage per character if all 8 hits connect). Doesn't seem to use anymore below 50% health?
Hades Blast: 270 MT physical damage
Maragidyne: 200 Fire damage, MT
Grand Tack: 280 gun damage
Megidola - 220 Almighty damage, MT. Won't use until < 75% health.
Ancient Curse - Inflicts Poison, Bind, Sick, Sleep, & Panic, MT.  However, if one/some of these status are nulled, the entire attack fails (e.g. a demon with Null Mind immunes only Sleep & Panic, and thus immunes everything.) Won't use until < 75% health.
Mamudoon - 55% Darkness ID, MT. Won't use until < 50% health.
Deceit Chain - 180 almighty damage, MT, inflicts Bind at ~50% rate.  Won't use until < 50% health.

Conversation triggers:
75% health: "There's no rush like fighting - you're getting worked up too, huh?"
Grin dauntlessly: +2 Attack for Kenji
Show pained expression: +1 Attack for Kenji, -1 Defense for your entire party
Grin menancingly: -1 Defense for Kenji
Ignore: Nothing happens
50% health: Blah blah fighting sucks, no wait fighting is my life, no in-game effect.
25% health: Kenji dies, and the remote you want is in reach?
Go for the remote: No he wasn't dead, and he sneak attacks you for 300 HP damage, ~70 MP damage to the party, inflicts Sick upon the party.
Don't go for the remote: All Kenji's stats down -1 (Atk/Def/Hit).

--
High Godlike despite not being as scary in-game as he looks (no Silent Prayer, and your buffs & debuffs are really good at this point, so you can and should stack 3x Luster Candy & 3x Debilitate to make his damage/durability/accuracy suck.).  Even if you lose entire rounds to the status, he can't kill you that fast post buff/debuffing his damage to a 7HKO per action.  His weaknesses are a tad annoying (a tanky Godlike PC might theoretically do something like Fire Attack > Full Heal -> repeat) but not nearly as crippling as for other SMT4 bosses.  3x Grand Tack is great damage for slugfests, and tanky PCs who are also paralysis & ID immune still need to kill fast lest they get 2HKO'd.

--

PC HP: Irrelevant
PC damage: ~400 (no guest)

King Ahazuya of Mikado aka Red Knight 
Crimson Catastrophe Cult Cavalier
"And now... I order you to become a sacrifice to the Overlord Prinny Baal!"

Type: Human
HP: 3200? (~.80 PCHP)
Reflects Lightning
Nulls Light & Dark
Went first 2/4 times
~10% evasion

2 actions per turn

Pandemic Bomb: 70% chance of Sick, MT
Mudoon: 55% darkness ID

AI notes: Opens with Pandemic Bomb->Mudoon, then spams 2x Mudoon forever
--
Have Dark-immune character, hit auto-battle.  Unfortunately a Heavy off turn 1 ID and okay speed despite literally no backup plan, which is way too good for a warm-up fight (ST ID is not impressive in-game).

He has an earlier form I didn't take notes for (because he appeared to be a random scrub.  Which he kind of still is.).  Also the boss you fight afterward is randomly more badass than either final boss, go figure.  (Maybe he was balanced for aftergame.)

--


Isabeau
"Such a loving couple...  Was death truly the only way for them to be joined?"

Stats: ????

Isabeau is only fought on the Law & Chaos routes.

--

Level: Flynn L78, relevant demons 67-83
PCHP: 710 (w/ Doping: 920)
PC damage: 400 (guest damage: 250)


Jonathan aka Merkabah
Order-imposing Huggable Neko Chariot
"I, too, have a confession to make.  I am a cat!  Meow!"

Jonathan is a two-part fight.  Once form 1 is defeated, there's a cutscene, followed by fight 2.  All buffs are reset, HP/MP isn't restored, but it's a fresh new turn for you.

Jonathan Form 1
HP: 6000 (~1.30 PCHP.  With buffs, ~1.10 PCHP.)
Type: Herald
Nulls Light & Dark
went first 0/4 times

3 actions per turn

Attack: 100 physical damage
Chariot: 220 MT Almighty damage, -1 to Hit/Evasion if it hits
Deadly Wind: 220 Wind damage
Thunder Reign: 220 Thunder damage, MT
Riot Gun: 200 Gun damage
Dekaja: Dispel enemy stat buffs, MT
Luster Candy: Buff Atk/Def/Hit +1, MT.  Never seems to use this unless he's already been debuffed.
Concentrate: Next Magic Attack increases in power by 2.5x.  Can only do this as his final action.

Conversation Triggers:
50% health + start of turn: "Answer me this,(blah blah rebel): For whom do you wage this battle too severe for a son of man?"
"For the people of Tokyo" - Flynn's Atk/Def/Hit +1
"For my old friend" - Flynn's Atk/Def/Hit -2
"For myself" - Jonathan gains 2 half-turns this round
"...." - Jonathan's Atk set to +3

Jonathan Form 2:
HP: 9000 (~1.95 PCHP.  With buffs, ~1.50 PCHP.)
Nulls Light & Dark
went first 0/4 times
3x actions

All of the same actions as Form 1, but gains...
Shalt not Resist: 2x unfocused hits of 150 Almighty damage each randomly to the party.  Each hit inflicts -1 Def (so if hit twice, the target has -2 Def).  The Def debuff doesn't instantly apply to the 2nd hit (so it'll be 300 damage the first time in a duel, and 420 the 2nd)
Hexagram: 100% Almighty instant death.  Absolutely loves to cast this on the guest, to whom it does nothing.  Uses very rarely in general - possibly an HP limit?  He was 4/5 on uselessly targeting Isabeau..

Conversation Triggers:
75% health: (blah blah darkness pierced by light)-> Jonathan gives Flynn a stern and piercing stare...
Stare back -> -2 Hit for the entire party
Smile back -> -2 Def for the entire party, Sick inflicted on party
Look away -> -2 to Atk/Def/Hit for Flynn
Quietly accept it -> Flynn is awakening to unlimited power!  Full HP/MP recovery, Atk/Def/Hit set to +3
33% health: Blah blah, how can I be losing, no effect.

N.B. Best damage in form 1: 3x Chariot =660.  Over 2 turns, Chariotx2 + Concentrate -> 3x Chariot = 660 + 770 = 1430.
Best damage in form 2: 3x Shalt Not Resist = (300 + 420 + 480) = 1200.  Over 2 turns, 1200 + (480*3) = 2640.

--

Jonathan is only fought on the Neutral & Chaos routes.  I don't believe his stats change on Chaos, where he's the final, but the conversation options do (no unlimited power for Demon Lord Flynn).   Also if you care the "correct" dialogue options are heavily hinted at earlier ("whoa, so you're accepting both Law & Chaos without embracing either?  That's so cool" etc.)

Kind of a disappointment in-game, really.  Damage not much better than Yuriko and worse than Kenji despite being fought with way more levels when you have elemental resistance out the wazoo and better buffs/debuffs in Luster Candy + Debilitate?  Shalt Not Resist is less impressive in-game than in a duel, too.  That said, a solid Godlike anyway in the DL.  His HP is just enough that it's hard for Godlike PCs to go first and OHKO each form, and Shalt Not Resist spam is pretty badass when focused on a single character, killing most PCs without need for Hexagram nonsense.

--

Flynn lvl. 81, relevant demons lvl. 80-84
PCHP: 750 (975 w/ Doping)
PC damage: 430 (no guest)



Walter aka Shirtless Chromaka Lucifer
Child of Carnage
"You and me are going to make a world where anything can be changed if you have the will."

Walter is a two-part fight.  Once form 1 is defeated, there's a cutscene, followed by fight 2.  All buffs are reset, HP/MP isn't restored, but it's a fresh new turn for you.

Walter Form 1
HP: 6000 (1.40 PCHP.  With buffs, ~1.15 PCHP.)
Type: Tyrant
Nulls Light & Dark
Went first 0/6 times
~96% accuracy on his moves (aka notably bad accuracy once you start buffing up, he doesn't start with overkill accuracy).  ~5% critical hit rate though (he clearly has some Luck.)

3 actions per turn

Attack - 170 physical damage
Evil Shine - 240 Almighty damage, MT, inflicts Panic 70% if it hits (but seemed more like 90% to me)
Hades Blast - 320 physical damage, MT
Myriad Arrows - 2-4 unfocused hits of gun damage, 120 per hit (avg. 360)
Glacial Blast - 1-4 unfocused hits of ice damage, 120 per hit (avg. 300)
Dekunda - All stat debuffs removed, MT
Debilitate - Debuff Atk/Def/Hit -1, MT.  Only seems to use vs. buffed opponents.

Conversation Triggers:
50% HP + start of Walter's turn: "For whom are you fighting this relentless, dreadful battle?"
"For the people of Tokyo" - Flynn recovers all HP/MP
"For my old friend" - Flynn's Atk/Def/Hit -2
"For myself" - Walter gains 2 half-actions this turn
"...." - Flynn's Def set to -3

Walter Form 2
HP: 9000 (2.09 PCHP.  With buffs, ~1.55 PCHP)
Nulls Light & Dark
Went first 0/6 times
~96% accuracy on his moves

Keeps the above moveset, and gains...
Kingly One - Return a PC demon to the stock (where it is still alive and can be resummoned). Doesn't work on Flynn (but he'll sometimes try anyway and Miss and lose a turn!).  Probably should only work on Pokemon or the like in the DL.
Morning Star - Almighty attack that cuts HP in half, rounded down.  Can't seem to use more than once per round.  (Also, like everything else in the game, can miss.)

Conversation triggers:
75% Health + Start of your turn: Blah blah blah... "I shall demonstrate why it is that you can never surpass me."  Walter gives Flynn an evil and overbearing stare...
Glare back intensely - Flynn's HP->1, MP->0
Stare back calmly - "Flynn awakens to unlimited power."  Full HP/MP recovery,  Flynn's team gains an additional 2 half-turns (!!!).
Quietly close your eyes - You skip the entire turn.
Silently look away - Flynn's Atk set to -3
33% Health - Blah blah oh no humans are more powerful than I thought.  No gameplay effect.

--

Walter is only fought on the Neutral & Law routes.  I don't believe his stats change on Law, but the conversation options do.  (No unlimited power for Flynn, but some lesser boost for the "right" option.)

Also kind of disappointing.  That Myriad Arrows / Glacial Blast / Hades Blast damage is naive, I would certainly assume some base level of resistance at this point - you can be fusing demons like Metatron which resist everything - which would make them more on par with Evil Shine spam.  Those Conversation Triggers are also brutal if held against him - ouch about handing out free healing & 2 extra turns.  And like all SMT4 bosses, he fears good evasion.  Still, he clearly slugfests well against Heavies, and Panic (while a crappy status) will eventually screw up stally PCs, so Low Godlike it is.

(Also, Walter & Jonathan are amusing parallels in their buff / debuff woes.  Jonathan can Dekaja your buffs but is stuck with slowly trading 1:1 with Luster Candy vs. your Debilitates, while Walter has Dekunda if you stack too much debuffing, but can't really efficiently deal with your Luster Candy spam.  Meanwhile, Yuriko, much earlier in the game, laughs at both since she sensibly has Silent Prayer.)

--


Sister Gabby aka Gabriel
Digital Downloadable Deva Diva
"The Lord has authorized me to offer you a special deal: for a limited time only, it's only $2.49 to fight me!  Amazing!  Act now!"

Stats: ????

Settling up with Gabby is DLC-only.  Alas.

[SnowFire]

There is one notable PC in SMT4, and unsurprisingly, he is a trainwreck.  Less of one than the Nocturne Demifiend (which was in NR!) thanks to Demon Whisper system making customizing his skillset less FAQ bait, but still trainwrecky none-the-less.  I'm going to give my suggested version of Flynn first, and talk about the variants & other interp calls afterward.  (Well, not quite.  I'd personally prefer Renaissance man Flynn that spread his stat-ups equally every level, but that's not what I have, so oh well, speedy samurai mage Flynn away.)



Suggested HP average: 654
Suggested damage average: 430
Suggested agility average: 95
Suggested base resistance: 13%

Flynn
Level 81
Type: Samurai
HP: 999
MP: 344
STR: 10 DEX: 10 MAG: 279 AGL: 181 LCK: 70

Sword: Excalibur
Gun: #1 Bazooka (1-4 hits)
Ammo: Shinno Rounds (~25% chance of ID)
Head: Hero Gray (+35 HP, +9 Mag, +3 Str/Dex/Lck)
Upper Body: ??? (varies by match, 10-25 HP, sets elemental resistances/weaknesses.  See below.)
Lower Body: White King (+101 HP, +7 Agl)
Accessory: Flaming Spirit (+230 HP, +52 MP)

Nulls Light naturally (=ID resistance).  Depending on equipment, will usually resist 1-2 elements of his opponent's best damage and be weak to a single element of his choice, at little HP cost, or else resist Darkness if he's facing an ID-slinger.

Speed: 2.2 std. deviations above average on first turn.  Trades rounds afterward (= average speed).
Overkill accuracy w/ that Agility.  Flynn can be nailed by -3 Hit debuff and still never miss.  (So 130%+ accuracy or so, to estimate?)  Slight dodge rate (~8%?).

Megidolaon (60 MP) - 530 Almighty damage, MT
Deadly Wind +1 (22 MP) - 520 Force damage to one
Diarahan +2 (15 MP) - Full healing to 1 target
Doping (45 MP) - Increase Max HP by 30% until end of battle, MT.  Does not provide healing.  Undispellable by anything in-game.
Die For Me! +4 (44 MP) - 95% (+4) MT Instant Death, Darkness element (+0: 80% rate)
Energy Drain +5 (9 MP) - Drains 105 HP & 105 MP from an enemy.
Concentrate (11 MP) - Next Magic attack does 2.5x damage
Luster Candy +3 (47 MP) - Buff Attack/Defense/[Hit+Evasion] +1 each, MT.

Other spells Flynn would like but he only has room for 8 slots:
Amrita (20 MP) - Clear all status ailments, ST
Debilitate +3 (47 MP) - Debuff Attack/Defense/[Hit+Evasion] -1 each, MT.
Judgement Light +4(44 MP) - 95% (+4) MT Instant Death, Light element (+0: 80% rate).  (This spell is slightly easier to farm to +4 than Die for Me!, if it makes any difference.)

Spells that aftergame Flynn slots in:
Antichthon (80 MP) - 640 Almighty damage but against a higher damage average, Debilitate effect (=Debuff everything -1), MT.  The damage is still probably better for Flynn.  (640 comes from assuming lvl. 90 Flynn has +35 to his Magic score and via the magic damage formula, not tested.).
Salvation (50 MP) - MT Full healing & status curing.  (Does not reset debuffs, though.)

..although Salvation does make Flynn easier to run out of MP in heal-lock situations than Diarahan, so who knows.

Spell that Flynn sets if you let him summon demon PCs from the stock (don't do this):
Bad Company (15 MP) - Summons the 3 highest level demons from the stock to go mock the solo damage average.

Other moves:
Attack: 140 damage.  (Can tank this damage to get a chance of ID by equipping the Chainsaw, ?% ID rate.)
Shoot: 1-4 unfocused hits of 65 damage each, ~25% chance of ID per shot.  (On average, ~50% chance of ID.)
Talk: Attempt to permanently recruit an enemy.  Assuming you pick responses randomly, ~50% chance of recruitment; goes up if Flynn purchases an App that makes recruit conversations easier.  Fails on all humans, bosses, & demons controlled by another human in the battle (e.g. a Hunter & his demons).  Probably should not work in the DL except on duelers with explicit vulnerability to recruitment (wild Pokemon, FFT generic classes / monsters, etc.).  Also note that SMT4 rando-demons appear to have the intelligence of canned pineapples, if that makes any difference to you.
Item: Use an item.  Arguably sort of legal, only Flynn can use all items naturally, other demons need to set an ability slot, and even then have to pick healing or offensive items (to use both requires both abilities be set).  I'd still not allow this by default.  If you do... only thing that really matters is getting a supply of 10 Beads & 10 Holy Fruits for MPless full ST healing, the storebought attack items are not worth it at endgame.  Flynn also gets 25 Detox Solutions & 25 Dis-poisons to heal Poison & Sick, & Patra stones to cure Sleep/Panic/Bind…  although he doesn't care in the case of Panic, and Sleep/Bind don't give him a turn to use it if didn't naturally wear off, so usually pointless.

Obvious Godlike.  Nasty instant-death even if you see all SMT4 characters as average speed, and if you do, then Flynn pumps a lot of those Agility points into Magic for more damage (if you let him).  Otherwise, a tanky staller, he resists your best damage and can cheaply full-heal, and make himself even tankier in the long term with Doping & Luster Candy.  Or he can just 2HKO you with Concentrate -> smash.  He's not a fan of non-ID status, though.  Even if you let him have Salvation, it won't really help against stuff like Petrify or various other nasty PC-killing statuses which is something that does come up in Godlike quite a bit.

[SnowFire]

Nitpicky stuff for Flynn.

HP averages: For bosses, I was using Flynn + 3 demons, 1 of each "build."  For Flynn himself, it's not clear how many demons he should be held against (the more, the better for him, because the demons get lower & lower level and Flynn's own tankiness counts less against him).  Anyway, lvl. 81 Amaterasu (426 HP) + lvl. 80 Maya (627 HP) + lvl. 78 Koga Saburo (735 HP) gives a decent baseline of 596 HP as the "demon" average.
HP avg. (Flynn + 3 demons): 697
HP avg. (Flynn + 6 demons): 654
HP avg. (Flynn + 9 demons): 636 (Actually should be even lower due to digging up low-level demons...)

Damage average: ARGHH.  Scaling Flynn against some "DL legal" demons overinflates him because you'll fuse good damage spells onto the demons who for whatever reason don't come with a good one, and also fuse around Pleroma / High Pleroma skills to pump it further.  Flip side, perfect demon fusion clearly isn't fair or realistic either.  I'd personally say just use the 430 4-character average I used above for the boss, and then shift this around appropriately for your views (if you use perfectly grown demons, it's more like 550; if you use DL-legal demons, it's more like 300, or even lower if you use a larger-than-4 demon average).

Agility average: Um.  Not very relevant if you only use Agility as a tiebreak between average-speed characters, of course, although 1st-turn is so important - complete with a stat that scales up & down like other RPGs - that I'd be inclined to treat getting that first turn as similar to your average turn-based agility.  In-game you don't care about the speed of non-Flynn PC demons, of course, but they're useful as a proxy for enemy demon agility, which is what really matters. 
Agility avg. (Flynn + 3 high level demons I had spread among Agl builds): 109 (std. deviation: 49)
Agility avg. (Flynn + 6 highest level demons I had): 95 (std. deviation: 39)
Agility avg. (Flynn + 10 highest level demons I had): 89 (std. deviation: 32)

Elemental resistances: It's kind of offensive that Flynn gets to double his durability every match unless he's facing an opponent with non-elemental magic or good variety.  Normally I'm not a fan of scaling such things, but in this case I think it's merited.  Since this is a case where using my own demons would obviously sway things, I looked at every single demon that joins from lvl. 76 - lvl. 84 (exluding DLC/route-specific/NG+/insanely obscure) and totalled non-Light/Dark resistances (including skills known by the demon itself, but ignoring ones from Fusion, even ones guaranteed to be available if desired).  Weakness counted as 1.5 (though it's really worse than this due to the extra turn), Neutral counted as 1, Resist counted as 0.5, Null/Absorb/Reflect all counted as 0.  I didn't do it for each type because I'm not crazy, but threw all of Physical/Gun/Fire/Ice/Force/Lightning in one bucket.  Result from the 23 demons used:
Weak   16 / Neutral 85 / Resist   23/ Null   4 / Repel   5 / Absorb   5
This adds up to 120.5 / (23*6) = 120.5 / 138 = .87, or 13% resistance on average.

So, when Flynn resists an element, he only takes .5/.87 = 57% the usual damage, rather than 50% the usual damage.  When Flynn doesn't resist an element, he eats 1/.87 = 115% usual damage.  (Non-elemental / Almighty damage doesn't get a boost for obvious reasons.)

Equipment options: Vast.  Check a FAQ or a list.  As a reminder Flynn nulls Light by default unless the armor overrides that.  A few highlights:
* Cream Pads: Resist Physical / Gun, Weak to Light/Dark (vs. brawlers without instant death)
* Magenta Pads: Resist Physical / Gun, Weak to Force/Ice (vs. brawlers without Wind/Ice)
* Tricolor Pads:Resist Physical / Gun, Weak to Fire/Lightning (vs. brawlers without Fire/Lightning)
* Black Demonica: Resist Dark, Weak to Force (vs. instant death slingers)
* Silver Rider, Blood Duke, Aquila White, Hero Red: Resist a non-Lightning magical element, Weak to an ID element (vs. enemies with 1 big element and elemental variety but no instant death)
* Lots of stuff: Resist any one magical element, Weak to a different magical element

As far as accessories, Flynn can take a 230 max HP hit to null any one status (Poison, Panic, Bind, Sick, or Confuse.)  Not much else of interest.

Aftergame Flynn goes shopping in the secret shop, and can basically NULL your best damage now in exchange for a weakness.  (In fairness, you can make maybe 1 purchase at the secret shop before the normal endgame, but certainly not the vast variety usually expected by the DL.)  Yes that includes Physical, the most expensive item for sale lets him Repel Physical too (when even resisting Phy is something Flynn can't do until toward the end of the game), so prepare for some insta-win battles. He can also pick up the Demonica Suit, which nulls Gun and has no weakness vs. the truly multi-talented who can exploit any weakness opening.  (This was my one purchase I scournged & sold stuff for in-game, since avoiding weaknesses is so key in-game.)  After-aftergame Flynn also can go shopping for Accessories and pick up an accessory that gives him a one-shot Auto-Life effect, if he'd die he goes to 1 HP instead.  Obviously fantastic in the DL, if you allow it, but it's all insanely expensive.  (Even *getting* to the Secret Shop costs 160,000 macca, and the best stuff all costs 200-300K macca, and Flynn is presumably rotating between these equips by match, so you bought a bunch of it.)

Stat-boosters: Every Mag/Agl/Lck stat-booster was used on Flynn.  If you've played the game, you know why; most PC demons stick around for 1-3 levels then get fused into something else.  You are basically throwing stat-boosters in the garbage if you give them to PCs comparable to a temp around for a single dungeon in other games.  You could theoretically save them all for endgame and then spread them equally then, but eh, this is comparable to saving all the bonus XP in Fire Emblem PoR/RD to spread equally with late-joining characters.  It's superficially "fair" but not really, you're basically handicapping yourself by not using them sooner.  Penalize Flynn some stats if you disagree (probably -30 or so to those stats).  (On the bright side, demons get an app ability that increases their stat-gain on level-up which is unique to them that Flynn can't match, so hey.)

A few notable interps I'm going to acknowledge but not talk much on:

* Devil Summoner Flynn - Flynn's version of "swap" is different from other demons, and is "Summon."  Other demons can only replace themselves; Flynn can put new characters on the field if there's an empty slot, or just swap other demons around in general.  Also note that in-game it's not a Game Over for Flynn to die, his summoned demons will keep fighting without him  If you see the Summon command as legal and let Flynn summon a bunch of pals who have the perfect spoiling / technique for the situation, he's an unrankable ubergodlike.  See: PB Marona, SN Reyva, FFX Yuna, etc.

* Lord of the Scrubs - Scale Flynn against every single demon in the game, including the 98% that you are expected to have used for a brief time then fused into something else. This interp is especially galling because if your heart really was set on using "old" demons at endgame, you'd use Fusion and/or Skill Mutation to get them some good DL-illegal abilities, so the averages are artificially deflated vs. in-game.  Not recommended, but if you do, Flynn has massive overkill damage and is ubergodlike again.  See: Radiata Stories Jack, or Pokemon w/ non-full evolutions in the average.

[NARFNra]

I think you might be wrong about resistance being half damage. It seems a bit stronger than that, Yamato Takeru was doing 75 damage with hits of his physical to my party and only about 20 damage to Catoblepas, which is very nearly exactly 25% normal. Anyway, I went ahead and got data on him since I happened to be playing through. I was gonna get more but I have some other stuff to pay attention to and the files been sitting untouched for a while so I figured I'd post it. I tried to do things as you did for this.

PC Level: 53 for Flynn, 48-53 for relevant demons
PC HP: 525 (w/ Doping: 682, although that's just a calculation)
PC MP: 195, though I didn't have many MP optimized demons. Would probs be about 20 points higher at good levels
PC Damage: ~255 ignoring resistances and ignoring de/buffs entirely (more noticable in this fight due to his ameno spam).  Guest offers ~170 ignoring resistances, taking into account that Critical Wave crits and misses a lot and he loves to spam it. His reliable move (agidyne) exactly hits that average.


YAMATO TAKERU
HP: 6400~ (2.15 PCHP)

Race: Famed
Repels Lightning
Nulls Light, Dark
Never goes first?

2 Actions a round.

Cross Dressing: No one seems to know what this does. It doesn't cleanse buffs, change resistances, boost crit rate, or anything. Someone claims it changes Alignment, which has only affects 3 skills you shouldn't even have yet and would need a New Game + to confirm. Just assume it's a charge turn.
Physical: 1-2 hits of 75 physical damage.
Homeland Song: 2-3 hits of 90 almighty damage, random target. Only used after Cross Dressing.
Ameno Murakumo: 150 MT almighty damage, target attack -1. Above 50% HP he only uses this after Cross Dressing or after a Physical attack. Below 50% HP he can use it in conjunction with either Berserker God, a Physical, or itself.
Maziodyne: 180 lightning damage, MT. He doesn't use this too often, the only time I ever saw this used twice in a row was under 25% HP on half turn.
Berserker God: 275 physical damage. Only used below 75% HP.

75% Health: "Know you cannot compare to me, who holds a nation on his shoulders. I protect the people."
You're Authority's Servant: Yamato Takeru gets +1 Atk and +1 Def
You're Tayama's Slave: Yamato Takeru gets -1 Atk

50% Health: Would you let this happen if you were the ones the law benefitted?
Yeah: Yamato Takeru gets -1 Def
Nah: All of Flynn's stats -1

25% Health: How can you go against law? Walter- "because STRONG"
In game, this is the point where Yamato Takeru seems to stop following a rigid pattern and just does whatever.
Also, I've never seen him critical above 25% health, but below it he suddenly seems to critical with his physical attacks about 50% of the time? At this point he starts getting a lot of crits when they would give him turns, but not after. I don't know if this is just bad luck or a legitimate stat change.

---------
Overview: Utter scrub in game due to buff abuse rendering his damage useless, but in a duel he's a bit better due to multihit focusing and whatnot. Yamato Takeru has a fairly reliable 2HKO in the form of Attack->Maziodyne, or Maziodyne->Maziodyne if you allow that, and after losing 1600 HP (0.5 PCHP) he can switch those out for Berserker God to really drive things home. Against targets that resist or null physical attacks he has a backup 3HKO with Homeland Song. Ameno Murakumo isn't really all that great but a reasonable almighty option and reliable MT. If you allow the critical phase he can pump out a lot of damage should he end up below .6~ pchp, which isn't too unlikely.

Just like in game, Takeru doesn't hit very hard and has trouble getting through buffs and healing. On the plus side, though, no weaknesses! I think he ends up somewhere in Middle.

EDIT: Actually, with decent durability and a 2HKO, he might end up somewhere in Heavy...