The number of Tonberries the player needs to defeat to engage the Tonberry King is 20–50. Tonberry King's appearance depends on the "Battle Scene", being triggered in Scenes 0236 and 0237, both played at Centra Ruins and feature a single Tonberry as an enemy. Once the Tonberry dies, the King may appear if the player has killed enough Tonberries: in 0236 one must have killed at least 20 Tonberries, and in 0237, one must have killed at least 50. Meeting this minimum threshold, and being in the right Scene, triggers the King's appearance every time.
The player may leave the area and save the game while in the process of killing the required number of Tonberries. Killing them consecutively is not required. Carding the Tonberries does count as defeating them for the purposes of summoning the King, but Tonberry King will not appear in a battle where the Tonberry is defeated by carding.
"It's Sharp!" is a single-target attack using the equation of a target's enemy kills multiplied by 30. "Junk" is a counterattack made after every fifth attack the party deals against Tonberry King that sends items falling down on the party for a random amount of damage. The items are pot, a kettle, a bottle of wine, cups, soccer ball, and a television. On top of these, Tonberry King uses a regular physical attack.
One might want to wait till the party's average level exceeds 30 before engaging Tonberry King, as he is one of the rare enemies to have Full-life in his Draw list. It is possible to escape the battle, transfer all Full-life to inactive party members, resume hunting Tonberries, find Tonberry King again, and draw another complete set of Full-life.