To receive high levels of AP for the party, the player should customize their weapons with the Triple Overdrive, Triple AP and Overdrive → AP abilities, and place two characters' Overdrive in Comrade mode, and one character in Stoic mode.
While fighting Don Tonberry, the player should cast Haste on everyone and then get Don Tonberry to counter with Karma the character whose Overdrive mode is Stoic, then revive him/her with the other party members and recast haste. The player should repeat this until Don Tonberry is dead or gets too close and the player is forced to flee. When Don Tonberry counters with Karma, the damage will fuel the Overdrive, which will triple and then convert into AP, and at the end of the battle the total AP is also tripled. The AP is received even if the player escapes the battle, or the Overdrive gauge is full.
It is possible to go from 0 to 99 Sphere Levels in one battle with three characters using this method; it is only limited by the party's MP and how fast Don Tonberry closes in. The amount of Overdrive received is determine by the amount of damage received which, for Don Tonberry, is the number of monsters a character has killed multiplied by 100. Only the Overdrive > AP ability is needed for this trick, but the other two abilities will boost the amount of obtained AP. The only character that needs to receive damage from Karma is the character whose Overdrive Mode is set to Stoic, meaning one can easily level up a weak character by skipping their turn and having a strong healer and a character who has had a lot of kills to perform the trick.
