+30 Bonus to HP at level up.
Description
HP Bonus is a support ability that gives a permanent stat boost to the user's HP while they gain a level with the ability equipped. It can be used for stat-maxing and level grinding to have higher maximum HP even without HP junctions.
Obtained[]
HP Bonus is learned by the Guardian Forces Brothers and Cactuar. Brothers is obtained by fighting Sacred and Minotaur in Tomb of the Unknown King. They can then learn HP Bonus for 100 AP after mastering HP+80%, which itself becomes available after mastering the lesser HP+% abilities (the player can master them instantly with Regen Ring, Giant's Ring, and Gaea's Ring).
Cactuar is recruited by defeating Jumbo Cactuar on Cactuar Island, reachable on a flying transport, and already has every type of Stat Bonus ability learned.
If the player removes HP Bonus with Amnesia Greens, there is no way to get it back.
Mechanics[]
HP Bonus gives the user +30 HP on top of their normal stat gain when they level up with the ability in effect. When the user is on Level 100, the ability will be ineffective.
Use[]
HP Bonus is perhaps the least important of the stat bonus abilities, as HP is a stat easily maxed without min-maxing with HP-J and HP+% abilities; junctioning 100 Full-life or Ultima to HP-J gets the player to very high health without needing to do anything else. However, if the player were to level up Squall from Level 7 to 100 with it equipped, they would get +2790 to their total, not an insignificant amount.
If the player wants to grind their HP via leveling up, the player can set Brothers to learn their HP abilities as soon as recruited to unlock HP Bonus at the earliest, and use items to learn the HP+% abilities where possible. The best min-maxing strategy is to remain on a low level until the player gets Cactuar and then level up with numerous Stat Bonus abilities in effect simultaneously.
As a character can have maximum four support abilities in effect at once, the player cannot ever co-equip all Bonus abilities: HP Bonus is likely the one worth leaving on the wayside in favor of Str Bonus, Vit Bonus, Mag Bonus, and Spr Bonus. After getting all Bonus abilities, a fast leveling up place is on Island Closest to Hell where the player can quickly defeat enemies with Quistis's Degenerator and Death spells in ST-Atk-J even with a low level party. To avoid leveling up before the player has all Bonus abilities, the player can have KO'd party members, escape random encounters, equip Enc-None, and use Card and Petrify to defeat enemies.
Min-maxing is unnecessary for a normal playthrough, even for superbosses, but will make the party noticeably stronger by the end and thus the game easier. The only time the player needs a full 9999 HP is for surviving Omega Weapon's Megido Flame. The character's maximum HP determines damage from Kamikaze, so if the player is using this ability they benefit from high HP as well. Other means of boosting HP are with HP Up item and by devouring a Level44+ Ruby Dragon.
As bosses do not give EXP, before engaging one the player should swap their Stat Bonus abilities for percentage stat boosts or other useful support abilities like auto abilities.