Fire Emblem Three Houses: Mage playthrough
Mages are an interesting class line in FE3H, since they play quite differently from fighters. I did this playthrough, using entirely mages, to get a pure sense of how good they are. My kneejerk is that while mages may not be quite as good as the best physical units (i.e. fliers), they're still pretty darn good, so I wanted to see how they would do when they had to shoulder 100% of the combat burden.
The rules are straightforward:
1. Everyone must be a magic user. A magic user is someone who is either:
(a) in a class that can use magic. Commoner/Noble is included here. War Cleric/Monk is NOT considered a magic class, because its main selling point is Fistfaire, which would enable physical setups. Trickster is probably fine.
(b) in a "physical" class, but all weapon attacks they make are magical, either via a magic weapon (Levin Sword, etc.) or a magic combat art (Frozen Lance, etc.)
2. Skills which enhance specifically physical damage (i.e. Str+2, Death Blow) are banned. This probably isn't necessary, but it avoids silly loopholes like making Levin Sword-wielding Brigand in order to hit things with a brave weapon really hard as a Mortal Savant or Dark Knight later... not very magical!
3. As is my standard practice, I'm playing Maddening NG, no free DLC rewards, no grinding or extra battles aside from quests and paralogues.
Note that I am allowed to use physical weapons if in a magic class (it's a legitimate advantage of mage Edelgard or Sylvain that they can deal decent physical damage), and am allowed to use physical gambits (due to a limit on the number of magic battalions, this is kinda inevitable).
I'm playing with the DLC because that gives me two extra mages out of the gate, and some extra class options. I don't think this vastly changes the playthrough, just makes it more enjoyable.
I'm playing on Crimson Flower because (a) three student mages out of the gate, (b) Hubert is better than Flayn, (c) Edelgard is the best mage of the lords, and (d) I just like CF okay. However, the playthrough would work similarly on other routes, I'm sure.
Playthrough notes:
-In Chapter 1, I use Linhardt, Dorothea, and Hubert. Byleth and Edelgard are still physical units at this point. The map proceeds largely as normal. Being able to magically bombard Dedue to death is a big help! I do have to watch my offensive spell limits, and everyone occasionally pulls out a weapon.
-In Chapter 2, I recruit Sylvain, Constance, and Hapi, giving me a team of 8. I add Bernadetta for chip damage. I do the required seminar with Hanneman, because Reason is very important. Hubert gets Mire, Edelgard and Byleth still haven't reached D though. This chapter proceeds largely as normal and isn't difficult. Edelgard hits Level 5 and can unlock Monk.
-In Chapter 3, Byleth, Edelgard, and Sylvain reach D reason, so everyone is a mage in truth now. The map draws some divine pulse uses due to fog nonsense. However, I'm very appreciative of the fact that all my attacks ignore terrain evade bonuses. A straightforward map, everyone hits Level 5 and there's a mass migration to Monk. One annoyance is that there are relatively few +mag battalions; I hand them to the units with highest charm because their gambits are good, usually Dorothea and Hubert (Edelgard and Byleth have high charm too, but can actually benefit from +str).
-No problems with Chapter 4; with everyone's spell uses having doubled I can be very flexible in my strategy. I recruit Lysithea in this chapter, and use Marianne as Mission Assistance so I have a second Physic user.
-In Chapter 5, I build up the Cethleann and Macuil saint statues, and I do a pair of quest battles during one weekend, which is enough to get Edelgard to Level 10 with Draw Back and into Mage. The story map is perhaps the first that feels at all more difficult than normal, just because the Pass reinforcements can kill a large number of my team. Still, with three Physic users now (Marianne as mission assistance again, plus Dorothea), I have immense flexilbility healing. The boss poses no particular difficulties. Most of my units master Monk by this fight's end, but not everyone.
-In Chapter 6, I grab the Lance of Ruin at the start, and give it to Hubert. I also recruit Marianne (who backtracks to Monk immediately; Priest sucks) and Annette. Both participate in the story battle. I have five people with Physic now! Hubert and Dorothea handle the archer passageway easily, and ignoring the evade terrain in the west and northwest is very useful! No problems at all with this map. The last few mages I've had since the start master Monk here.
-In Chapter 7, I recruit Mercedes, completing my roster of student mages. I bench Sylvain (who isn't turning out well) and Annette. Gronder is quite tricky, mostly because of Ingrid and her pegasi. I realize I have no great answers for pegasi on my team: they have solid res and I have no bows. Lysithea's Luna, Edelgard's Smash, gambits, and magical combat arts are my most effective tools. Ingrid is a stat monster but I lure her beside one of her allies and gambit that one, then pick her off the next turn. Nothing else on the map is too bad, though Claude is noteworthy because he's a rare enemy I can't outrange (other archers can be hit at range 1, while those with 1-2 weapons like Hilda can be hit at range 3).
-In Chapter 8 comes a new set of battalions, very helpful! Empire Mages (+mag, huge gambit) and Seiros Archers (no mag penalty, good hit, good gambit) are the most notable new pickups, and Hanneman bringing a third D-rank magic battalion is also nice. I do Lorenz's paralogue for Thyrsus; a reasonably tough fight (I don't warpskip it) but my big gambits turn the tide; I mop up the map and even get both treasures, along with the real prize, Thyrsus! Gloucester Knights are great too. I also do Sylvain's paralogue. The low move is something I notice here, but once again, I'm still able to get all the rewards. Thyrsus gets passed around like a hot potato; it's great. Finally, the story map presents no difficulty. Turn 1 Stride gets me into the action, Physic reaches the villagers so they don't die. The Death Knight dies to a combination of a Dorothea's Resonant Flames (100 hit against his bad charm, and stuns all his allies as a bonus) and Lysithea's Dark Spikes, while Solon gets chipped from range with Thyrsus and the finished off, so no worries about his crit.
-In Chapter 9, I do Sothis's paralogue. Like Chapter 7 this also exposes a bit of a weakness of mages: they're bad at tanking bird and wolf attacks (only Edelgard and Byleth can tank the wolves, and a few others like Dorothea and Linhardt can tank the birds too). Some clever gambit use is needed to approach the three birds in the south, and to deal with the two that fly in from the northwest. I realize that I could have used a combination of Hapi's personal and the Impregnable Wall gambit to cheese part of this fight, but only realize that halfway through, and I didn't bring that battalion. I also do Flayn and Seteth's paralogue; with my ability to ignore desert and Thyrsus-trading to cheese the water sections in the west it's very easy, even if the assassins kill anyone but Edelgard and Byleth if they could ever reach them. Dorothea/Ingrid paralogue presents no problems. Hapi/Balthus paralogue is a bit tricky as I relearn all the nonsense reinforcements, but by this point Dorothea (northwest corner) and Edelgard (central area) are strong enough to solo significant groups of enemies. The story battle itself presents little difficulty as nobody is doubled, and nobody is OHKOed except Lysithea, and range supremacy + taking advantage of barrier breaks allows me to take relatively little damage, while Physic removes any doubt that I will save all the students.
This is a good point for thoughts on units so far, since we haven't yet hit Level 20 or picked up any A-rank skills (or, rather, this was true early in Chapter 9, at least). Pretty much everyone went Monk->Mage, except the later-joiners. I maybe should have made someone a magic combat art pegasus knight for move, but oh well. Most units have hit B in key skills, but not A, so the comments reflect that.
Edelgard: Got RNG-blessed on speed so just has... really good stats that aren't magic (armour knight certification helped), and even her magic is okay. Not being weighed down by Bolganone is fun. My best tank and very versatile with her combination of axes and reason spells; Luna is a nice pickup, too.
Byleth: Edelgard but with worse power/bulk (and speed, though that's RNG) and no Luna. Unlike Edelgard she doesn't feel that useful, though is the second person I tap if I need to bait a dangerous-looking physical formation.
Hubert: Mire is 3 range which is fast enough to not be doubled by many archers, very flexible. His Frozen Lance hits quite hard, especially with the Lance of Ruin in a pinch. Accuracy is something he needs (outside of Fire), he often uses the Accuracy Ring. My only unit who hasn't learned Heal, but has Rally Magic instead (more useful than normal, this playthrough!).
Dorothea: Thoron, Physic, Hexblade, and high charm to land magical gambits with are all good, as usual. She decided to get RNG-blessed on magic as well so is really good, pretty easily my best unit except Edelgard (who is different).
Linhardt: Also got very RNG-blessed in both magic and speed, which makes him more useful than normal! But since his charm is garbage I've largely stuck him with the Stride battalion, limiting his offence. Has had Physic since early, though, and is accurate, and will get Warp pretty soon.
Sylvain: Was supposed to play a tanking role with Black Magic Avoid, but he got defence-screwed so that didn't work as I'd like. Since he also got charm-screwed there wasn't much reason to keep using him over other mages, even though he had Physic... his magic is just too much lower.
Constance: Not too much to say about her, she hits hard (with either spells or Soulblade) but has few tricks. Rally Magic for a time, though I've since shuffled that out now that I have Heal and Ward to give her plenty to do when enemies aren't in range.
Hapi: Has 3 range, though unlike others she can't use it on enemy phase much because of what it does to her speed. Her stat build isn't too hot and I'd like a magical combat art but Death + Physic is a solid combo. She'll probably be my Dancer because of the riding boon, but I haven't decided for sure.
Lysithea: As usual, very versatile offensively: Luna is great against mages and pegasi, Seraphim against monsters, Dark Spikes against cavalry. Probably uses her magic combat art the least just because Dark Spikes hits about as hard anyway (for now). So far she's been pretty limited in what she can do if no enemy is in her range, but she's about to get Warp so that will change.
Marianne: Thoron for reach, Physic for healing, Frozen Lance for melee, a solid charm stat... plenty to like here, even if she's been playing catchup and won't have Fiendish Blow for a bit longer still.
Mercedes: I got her a bit later (like Marianne, I just got her to B support then rolled the dice on her asking me to join), so she's missing Draw Back, but she still has Physic and decent stats. Doesn't stand out at all and probably one of my weaker units as such (really wants HP+5 for her tanking role), but good enough to stay on the team.
I'm looking forward to Linhardt, Lysithea, and Constance picking up Warp/Rescue! This playthrough has definitely highlighted that Draw Back, while good, is not as good as Reposition, so I do want more positioning options.