A lot of equips in MF6 have hidden factors that I can't fit into the item description and can't be looked up. This was always the case in FF6, except most equipment didn't get as complex as the shit in this game, so a simple item description was often all that's needed...not the case in MF6 however, so something like this is required:
If an item has a trait not listed here, its cause it can be found in game, either through its description or through the equipment stats. Items listed on Item Value, hence the "random" order; just Ctrl+F an item (I listed items in their full name and their in game name (if different) for convenience) if you want to see if it has a hidden effect; if an item is not on the list at all, assume its effects are all public (either via item description or can be checked on the items stats by selecting the equipment in the Item menu.)
Note that many (but not all) "unique" weapons are used by Laharl too, so if a weapon is Character/Laharl, its still "unique."
Weapon effects function like FF6 variants, unless specified otherwise, eg. "Random Casts" is still 25%, "Counter Attack" is identical to Black Belt etc.
All Rolf Uniques give +25% HP
All Fayt Uniques give +25% HP
All Tir uniques give +25% HP
All Ryu uniques give +25% HP and Counter
All Yuri uniques give +25% HP
All Shady weapons offer no HP Boost
Ginny's 2 Guns give no HP Boost
All other Weapons give +12.5% HP
NOTE: Naturally, there's an implied "unless specified otherwise" for the above.
Levantine: Random Casts Fire 3, Ignores Defense
Silver Sword: Counter
Rekscalibur: Randomly casts Black Shadow
Silvance: Teaches Divine Blade x2
Dragon Blade: X-magic, Magic Cost Half, MP Criticals
Divine Avenger (DivineAvengr): MP Criticals, randomly casts Ethereal Blast, teaches Etheral Blast x1, Enhanced Jump
Apocalypse: Randomly casts Dark Holy, MP Criticals, 255% Hit rate, teaches Ultima x1, Ignores Row
Golden Lion: Random "Slicing" instant death, Counters, randomly casts "Muddle"
Azelf Weapon: Auto Haste, Atma Weapon Effect
Beast Spear: +25% HP, Atlas Armlet Effect, Auto Siezure
Gungnir: +12.5% HP, Earrings Effect, Turns Fight to Jump, randomly casts "Tandle", 255% Hit
Onion Armor: Grants immunity to Poison and Imp
Bantorain93r: Halves MP Cost, Genji Glove effect, ignores Row, teaches Shield x10
Holy Sword: Teaches Divine Blade x3
Soul Eater: Earrings Effect, +12.5% MP, Instant Death immunity
Elysdeon: Offering Effect, Auto Safe, Gauntlet effect
Regal Sword: Counter Attack
Ragnell: +25% HP, Auto Safe, Hawkeye effect (random Throw for extra damage), Counter Attack, randomly casts Drain, ignores Row
Sky Fang: MP Criticals
Ranger Blade: Teaches Ogre Slice x15
Ruby Maser: Randomly casts "Fire 2", teaches Crimson Raid x12
Sapphire Master (SapphireMasr): Randomly casts "Ice 2", teaches Death Bringerx10
Plasma Maser: Randomly casts "Tandle", teaches Discharge x10
Gorun Nova: MP Criticals, randomly casts "Tyranitar", halves MP cost, raises Pre-Emptive Attack rate, No Back/Pincer Attacks, raises Steal rate, Sprint Shoes effect, doubles GP gained
Masamune: Teaches Tera Break x10, raises Pre-emptive Attack rate
Violet Blade: MP Criticals
Love Charm: +12.5% HP, +12.5% MP
Glance Reviver (GlanceRevivr): MP Criticals, Hero Ring effect, Counter, randomly casts "Osmose"*, teaches Nibelung Valesti 3 x1
Simple Sword: Teaches Divine Blade x1
Long Sword: Teaches Divine Blade x2
Rapier EZ: Teaches Protect x5, Halves MP Cost, Genji Glove effect, ignores Row, Valiant Knife effect (includes Defense Ignoring),
Broad Sword: Teaches Divine Blade x4
Veinslay: Teaches Divine Blade x5
Soul Sword: Ignores Row**
Wolf Fang Staff (WolfFangStff): Ignores Row
Heaven Fang Staff (HeavenFangSt): Counter, Ignores Row
Flamberge: Offering Effect
Diabolic Sword: Man Eater effect, Offering Effect, Gauntlet Effect
Last Fencer: +25% HP, Auto Regen, ignores Row
Falcon Punch: SOS Safe, SOS Shell, Earrings Effect, Auto Float
Regirock Block (RegirockBlck): SOS Safe, Blind Immunity, Auto Cover,
Regice Shield (RegiceShield): SOS Shell, Blind Immunity, Instant Death Immunity, Berserk Immunity, Sleep Immunity
Registeel Guard (RegisteelGrd): Blind Immunity, Poison Immunity
Arredoval: Auto Float
Stan's Shield: Auto Condemn, Auto Mute, Auto Muddle, Auto Berserk, Auto Seizure
Splinter Helm (SplinterHelm): +12.5% MP (just specifying for sake of stackability)
Judge Helmet: +25% HP (see above)
Captain's Hat (Captain'sHat): Atlas Armlet effect, Counter
Prism Crown: SOS Safe, SOS Shell, Auto Regen
Dragon Helm: Grants Immunity to following status: Blind, Zombie, Poison, Imp, Petrify, Instant Death, Mute, Berserk, Muddle, Sleep
Drifter's Coat (DriftersCoat): Offering Effect, doubles GP gained
Minerva: +25% MP, X-magic
Radiant Garb: Halves MP Cost
Quantum Cape: Auto Float
Seraphic Garb (SeraphicGarb): 1 MP Cost
Life Armor: HP Stroll, Immunity to Seizure
Aqua Wisp: Earrings Effect, +12.5% HP,
Firery Rage: Atlas Armlet Effect, Poison Immunity
Terra Roar: +12.5% HP
Bolt Materia: +12.5% MP
Ice Materia: +12.5% MP
Fire Materia: +12.5% MP
Gale Claw: Auto Haste, Counter
Vaynard SKirt (VaynardSkirt): Blind Immunity
Clive's Specs (Clive'sSpecs): Atlas Armlet effect
Drakkhen Tear (DrakkhenTear): Auto Condemn, Sprint Shoes effect
Fake Egg Ring (FakeEggRing): Allows for "Storm" spell
Hurly Glove: Allows for "Character Toss"
Buster Glove: Auto Regen, Auto Cover, SOS Safe, SOS Shell, Half MP Cost, Raises Pre-emptive attack, No Back/Pincer Attacks,
Joachim Belt: +50% HP (listed for stacking purposes)
Youthful Spirit (YouthfulSprt): Auto Regen, Sprint Shoes effect
COsmic Cog: Instant Death immunity, SOS Safe, turns "Steal" into "Capture", No Back/Pincer Attacks
Tyrant Fist: Atlas Armlet Effect***
Moon Spark: Sleep Immunity,
Cai's Book: Earrings Effect
Lance's Crown: +50% HP, Counters,
Dragon Orb: Halves MP Cost, Earrings Effect, +50% MP, grants immunity to Zombie, INstant Death, and Petrify, Auto Float
Dryst's Hat: Lowers Encounter Rate, Sprint Shoes effect, +25% HP, +25% MP, Auto Regen, Raises Pre-emptive ATtack
Quartz Charm: Auto Safe, Auto Shell, Raises Steal Success Rate
Lyonese Flail (LyoneseFlail): Atlas ARmlet Effect, +25% MP,
Flash Hit: +12.5% HP
Cardboard Box (CardboardBox): Auto Berserk, Auto Muddle
Ivory Charm: Auto Regen, Grants Immunity to Following: Blind, Zombie, Poison, Imp, Petrify, Instant Death, Condemned, Mute, Berserk, Muddle Siezure, Sleep
Hammer: Its the Back Guard
Cure Materia: +12.5% MP
Cupid's Lyre: Auto Regen, Siezure Immunity
*Osmose in this game is an HP Drain move that has 100% Instant Death attached; fails against those immune. There is no access to this move other than through random spell casting so I didn't bother changing its name.
**These are not intended and will likely be removed in a later update
***Likely to change to Hyper Wrist effect in future
Level up Chart, cause its different than in FF6!
Terra:
Level 1 - Cure
Level 3 - Fire
Level 6 - Antdt
Level 8 - Ice
Level 12 - Drain
Level 18 - Life
Level 19 - Fire 2
Level 20 - Break
Level 28 - Heal
Level 32 - Holy
Level 33 - Life 2
Level 34 - Fire 3
Level 36 - Ice 3
Level 40 - Quartr
Level 50 - Merton
Level 98 - Ultima
Note: A few of these spells can be learned through various equips.
Lenneth:
Level 1 - Nibelung Valesti
Level 4 - Analyze
Level 9 - Shield
Level 12 - Protect
Level 18 - Life
Level 20 - Nibelung Valesti 2
Level 22 - Heal
Level 29 - Remedy
Level 33 - Mute
Level 45 - Reflect
Level 51 - Nibelung Valesti 3
Note: A few of these spells can be taught via equips.
Yuri:
Level 10 - Die Scumbag!
Level 12 - Demon Rays
Level 13 - The End!
Level 15 - Hell Fire
Level 30 - For Tommorrow
Level 39 - Revive
Level 45 - For Everyone
Level 70 - For The Child (can be gotten via Plot sequence)
Vyse:
Level 1 - Incremes
Level 6 - Counter Stance
Level 12 - Pyres
Level 15 - Cutlass Fury
Level 24 - Skull Shield
Level 30 - Rain of Swords
Level 35 - Pirate's Wrath
Level 40 - Blue Rogues
NOTE: he's intended to get all these by the Falcon, but for some reason the Plot Trigger doesn't work right; I think he still gets them when Cyan would learn all his sword techs.