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WAR: Risk Strike. A low-accuracy critical attack which does quadruple damage and has the effect of Full Break.
MNK: Hokuto Hyakuretsu Ken. No explanation should be necessary, google it if you don't know what it already does.
WHM: Heaven Strike. Basically just a super powered Seraph Strike, so it's more useful?
BLM: Play Rough. Temporarily grants the BLM a Chainspell effect, useful for Magic Burst sequences.
RDM: Magic Weapon. A high damage elemental attack, the element is determined by the RDM's current En-spell effect.
THF: Shower Shank. The THF forces the target into the nearest corner, then shanks them between the ribs.
PLD: Heaven Blade. Similar to WHM, but with a sword.
DRK: Death Wave. A similar effect to Zantetsuken. If a mob is KO'ed, it's HP is drained by the user. Standard rules for Zantetsuken apply to NMs as they normally would.
BST: Throw Beast. The BST throws their current pet at the target, expending the pet's life for massive damage. Damage type depends on pet thrown, and damage done is partly determined by how much HP the pet had.
BRD: Instrument Bash. No explanation needed.
RNG: Spike Trap. The user sets a spike trap that can take up to 50% of an enemy's current health.
SAM: Throw Gil. Throw a set amount of gil at enemies in a frontal-conal AoE. The amount thrown divided by the number of enemies hit determines the damage done.
NIN: Substitution: The NIN disappears and is replaced by a log, and the NIN deals a critical hit from behind the enemy. The NIN loses enmity and receives a brief "Sneak Attack" effect.
DRG: Double Jump. A jump WS with two consecutive attacks, although this could just be another JA.
Sky Drop. The DRG grabs the target enemy, takes them up to the sky with them, drops them, then impales them with their weapon.
Heaven Cross. A Super Jump effect that ends in a single hit attack that does high damage.
SMN: To the Farplane. Yeah.
BLU: Cutlass Fury. A 4-hit WS more powerful than Vorpal Blade.
COR: Loaded Chamber. A 6-shot WS to be used exclusively with Hexagun type guns.
PUP: Throw Puppet. The user throws the puppet at the enemy, sacrificing the puppet in the process. Damage type and other modifiers are determined by puppet frame and head.
DNC: Beat It! The DNC breaks out Micheal Jackson moves which inflict various status ailments to the target.
SCH: I'm Smarter Than You. The user belittles the target to make them feel emotionally unstable and insecure. The target's stats are lowered.