|“||One route will lead you to Tortletummy. He's a big-bellied foe who keeps his treasure hidden. In his belly, that is. There must be some way to get it out of him.”|
|— Daroach • Kirby Mass Attack|
Tortletummy is a massive, obese green tortoise with small eyes, a wide red mouth, a smooth black shell, and a helmet on his head. He has a tail, small feet, two stubby arms growing out of his chest, and a protruding navel.
A purple Tortletummy also exists.
Tortletummy first appears in Stage 10 in Green Grounds and reappears in Stage 5 of Dedede Resort, as well as the Survival Rush sub-game. When the Kirbys find him, he is sleeping soundly. He rests in front of a door needed to complete the stage, so he must be defeated in order to advance. The player must flick one of the heroes into his belly. He awakens and, enraged, initiates the fight.
Tortletummy attacks by generating leftward-moving currents and launching small, electrified sea jellies through it, as well as fruits and air bubbles. Few jellies pass through, but if one touches a Kirby, he is electrified and takes damage. This first current is weak but only ends once Tortletummy has taken enough damage. Like before, the player must flick Kirbys into him to hurt him.
In his second phase, Tortletummy produces a strong current to push the Kirbys again the back wall. The current weakens as walls of larger jellies and some air bubbles drift through. The heroes should swim around the enemies and strike the mid-boss whenever they get the chance. After an extended period, Tortletummy sits down in exhaustion; this temporarily terminates the currents, offering the Kirbys an opportunity to attack him. If he starts another current after resting, small jellies and fruit are included in it. The third phase is the same as the second, though with slightly different enemy formations. Upon defeating Tortletummy, he bursts into air bubbles.
Tortletummy reappears in Dedede Resort, where his battle is slightly different. After he is done resting from his current attack, Thorn Tortletummys emerge from the left wall or floor and the mid-boss directs the flow toward them. The heroes must swim in the opposite direction of the current to avoid them; a single touch from a Thorn Tortletummy KOs a Kirby. After defeating Tortletummy, he spits out the stage's rainbow medal and bursts into bubbles.
Tortletummy's name is a portmanteau of tortoise, turtle, and tummy, referencing his species and obesity.
- Tortletummy is the only mid-boss to appear alive in two stages of Kirby Mass Attack. Big Warwiggle, Great Gear, and King Eelongo appear in two stages as well, but they are undead in their second appearances.
- Tortletummy is one of the few characters in the Kirby series who is confirmed to have a navel. The others are Mr. Frosty and Storo.
- The jellies Tortletummy summons resemble Mini Jellifrizzes but have two notable differences: They have four or six tentacles depending on the size, and neither variant has a cubic head.