They, along with Bonechill, were released from their imprisonment in the Underwhere by Count Bleck. They escaped from the dark realm and laid siege on the Overthere, in an attempt to capture the Pure Heart said to be held by King Grambi. As Bonechill took over Grambi's abode, the Skellobits—reaching as far as the upper reaches of the Overthere Stair—attacked and imprisoned the Nimbis. Coincidentally, the invasion began shortly before Mario and Luvbi reached the Stair.
A high-ranking Skellobit, it attacks by charging at the player with its spear. They can be defeated with Pixls, Bowser's fire breath, and Luigi's Super Jump (if Luigi is underneath).
A winged Skellobit with wings, it attacks by throwing its own head at the player. It quickly grows new heads, so it is able to keep on throwing them. It also sometimes carries Skellobaits or Spiky Skellobaits.
A teal, limbless skeleton dropped by Skellobombers. It crawls around on the ground and blows freezing breath at the player character if it sees them.
Variants of Skellobaits with spike-topped skulls that prevent the player from damaging them by jumping on them. Like normal Skellbaits, the Spiky Skellobait is dropped by Skellobombers and blows freezing breath at the player if it sees them.