Cel

Once upon a time, a random surfer dude from Lake Clearwater (same place Sanity came from) stumbled into the portal during a freak activation event triggered by a lightning strike. He then proceeded to wander Mysteria for an unknown amount of time, eventually coming into contact with Lucite that mutated him into what he is now. 

What is he now? Mostly the same as before, except for the fact that he goes through sudden and rapid mitosis on a frequent basis.  As of current time, there are enough Cels present in Mysteria to consider them a unique species. Notably, when a Cel duplicates, its clothes do also, but ONLY if those clothes happen to be: a hawaiian shirt, a white tank top, and a pair of swim trunks.

Another notable quirk of Cel anatomy is the fact that whenever one goes through mitosis, the age of both "child" Cels are biologically reset to 21.