Cloud
-) Gains +25 to strength or +25 to Magic when a command related to that damage type is used by either himself or a party member; this only unlocks after recruiting him again in Mideel.
Barret
-) When hit with physical damage, he will gain a stacking buff to either strength or defensive stats based on whether he is in the front row or back row respectively. Gaining a buff stack of one type will cancel all stacks gained for the other type.
Tifa
-) Once per battle, Tifa will auto-revive with 1HP when KO'd, retaining command input, limit gauge, statuses, etc. (this can work against her if she has Dual-Drain or Poison, however).
Aeris
-) When using Defend, Aeris will absorb Fire, Ice, Bolt, Earth, Water, Wind, and Holy elemental attacks; Poison, Gravity, and Hidden element attacks will still deal damage.
Red XIII
-) As a battle goes on, he will slowly gain Strength and Magic up to +50.
Yuffie
-) When hit by physical damage, she will gain an evasion buff; when hit by magical damage, she will gain a magic evasion buff. Like Barret, only one effect can be active at a given time.
Cait Sith
-) Will sporadically gain HP equal to his currently remaining MP.
Vincent
-) Slowly regens MP, which can go past his MaxMP
Cid
-) When attacked in the front row, Cid will gain Barrier (if he doesn't already have it) and MBarrier if he is in the back row.