Ameba are an enemy that was introduced in Drawn to Life: The Next Chapter for the DS, and acted as a replacement for Shadow Walkers. One also appears in Drawn to Life: Two Realms in the Galactic Jungle District of Rapoville.
However, when they were first seen back in 2009, there was no official name for the enemy, so many fans simply called them Ghosts. The name Ameba was only revealed in Drawn to Life: Two Realms.
Due to this confusion in the community, the Challenge Imagination Battle for the Ameba has the tagline:
"Walks, Talks, Acts like a ghost. But isn't a ghost. Squish it!"
Despite this confusion, the Drawn to Life Series is no stranger to ghosts, with ghosts of some kind appearing in every game in the series:
The Mayor's Ghost (Drawn to Life, Drawn to Life: The Next Chapter [DS])
The Flying Dutchman (Drawn to Life: SpongeBob SquarePants Edition)
The Ghost Creation (Drawn to Life: The Next Chapter [Wii])
Baki Pirate Ghosts & Baki Beard (Drawn to Life: The Next Chapter [DS])
Swoopers (Drawn to Life: Two Realms)
