The Hyper Wrist and Bone Wrist increases the wearer's Strength by 50%. Various Espers grants a permanent boost to Strength when the equipped character levels up.
Materia Fusion can grant ATK+ to Materia, increasing Zack's ATK up to 100 points on a single Materia. The SP Turbo and SP Turbo Attack Support Materia increase the damage done by Zack's attacks by 20% for each level of the Materia, but cause Zack to expend SP when he attacks.
Guardian Forces can learn Str +20%, Str +40%, and Str +60%. The Str Bonus ability increases a character's Strength by 1 on level up, and unlike the +% abilities the boost is permanent for that character.
The Battle Lore Augment on the License Board grant the character +1 Strength when taken. The Focus Augment increases damage by 20% when the character has full HP, and Adrenaline doubles damage when the character is at critical health.
The Power MAGI increases a Robot's HP by 99 and Str by 22 when equipped on them. Power increases the equipped character's Str by 5 and adds 1 point of Str to physical damage for each MAGI the player possesses.
ATK Boost has six different levels, each increases ATK by a greater amount than the previous level. ATK Grow, much like Str Bonus in Final Fantasy VIII, increases the amount of ATK the character gains upon leveling up, depending on the level the ability is at currently. ATK Boosts can be customized onto equipment via Strength Stones, while ATK Grow is customized onto equipment via the Small Ruby and Ruby.
STR +20% is the level 13 ability of the Warrior class, requiring 280 AP to learn. It requires 1 slot in order to equip and use.
Various accessories grant boosts to ATK. Some accessories and weapons grant percentage-based boosts to damage and physical damage.
When an Equip ability is mastered, the character learns an Adept (in Dissidia) or Master (in Dissidia 012) for that type of equipment. When the Adept/Master ability is equipped while the character has a weapon of the corresponding type equipped, the character has a +5% damage boost.
Strength Up comes in three levels of power, each level granting a larger bonus to Strength and damage during BMS sequences, but Lv 2 and Lv 3 carry a penalty to Agility. Strength Up Lv 1 increases Strength by 20 and increases damage during BMS to 1.1x times normal, Strength Up Lv 2 offers +40 Strength and 1.3x attack power but has a penalty of -60 Agility, and Lv 3 increases Strength by 65 and increases attack power to 1.5x normal, with a penalty of -120 Agility.