When Magic Booster is used in the 2013 PC re-release, the player's inventory gains 100 Confuse spells, among other basic spells.
Confuse can be drawn from a small variety of enemies, especially at levels above 20. It can be most easily refined from Betrayal Swords using the Guardian Force Diablos' ability ST Mag-RF. Forbiddens a good source of Betrayal Swords, as is their cards.
Confuse when cast will inflict the Confuse status effect on a target that is not immune to it. This renders the target unable to control their actions for its duration, meaning they will act randomly, even using random items on random targets if they have the Item command.
Confuse can be cast using the Magic command, Selphie's Slot Limit Break, or Rinoa's Angel Wing if she has it in her inventory. Casting Confuse in battle increases compatibility with Doomtrain by 1 and with Siren by 0.6, but lowers compatibility with Cerberus and Carbuncle by 0.2.
Confuse can be junctioned to ST-Atk-J to inflict Confuse on enemies with a physical attack, allowing a character to permanently inflict Confuse against enemies that are vulnerable to it. This can cause enemies to turn on one another. One humorous scene involving this effect is with Biggs and Wedge in D-District Prison.
However, a better use for Confuse is to junction it to ST-Def-J to resist against Confuse, and 100 Confuses immunize against it. This is especially useful against enemies that inflict Confuse, such as Malboros, as it can be a potentially devastating status. Due to this use of the spell, it is often better to stock Confuses rather than cast them.