Zeiram is an alien that is very large humanoid that wears a ragged cloak and a round hat. Its body is practically indestructible and if it feeds, it can regenerate quickly. It feeds by extending its face which is at the end of a tentacle and bites people. It can then generate weaker, smaller monsters from the genetic material it absorbs from its victims. Three of the monsters appear to be partial clones of whatever was killed in making them.