In Shroom City, this minigame is played at Bowser Hideout. Bowser challenges the player to beat this minigame after winning his card game. Winning Koopa Kappa gives the player the minigame and the Gaddgets Faux Flame and Hourglass.
The player must drop capsule lids on all the Koopa Kids who have the same button inscribed upon their transport as the lid by pressing certain buttons as the Koopa Kids move on the conveyor belt.
There are two conveyor belts; the Koopa Kids going along the top belt always are inscribed with one of the shoulder buttons, and the ones along the bottom and . When a capsule is dropped on one side, the player must wait before they can drop another. Dropping the incorrect capsule on a Koopa Kid has no effect on them. If a Koopa Kid makes it to the end of a conveyer belt without being trapped, they head into the room the player is in and drop one of the five plungers. If this occurs four more times, the barrier protecting the player rises entirely and they blow up, losing the minigame.
Names in other languages