31 favorite monsters: Raremon
While this is one of the creatures I've written about before, I can't resist repeating some of my favorites here. I do love my rotting, shambling heap-like monsters, and Raremon has possibly my favorite design of any rotting, shambling heap. Its comically vacant stare, lidless eyeballs and protruding teeth all contribute to a special horrendousness duplicated matched by very few other monsters, let alone other Digimon.
The original Digimon virtual pets each had many possible forms for your little critter to take, including a misfit "failure" or "garbage" form when you failed to clean up your monster's virtual feces. Raremon was the failure of Digimon version V, and originally depicted by a sprite with uncanny resemblance to Hedorah. In fact, when Raremon first appeared in the Digimon anime, it emerged from a harbor and attacked a nightclub in direct homage to a scene from Godzilla vs. the Smog Monster. According to the official lore, Raremon is a botched attempt by an organic Digimon to evolve into a machine Digimon, and its malfunctioning cybernetics are all that hold its mindless, rotting body together. Best of all, it attacks by throwing up!
The only downside to Raremon is that, like so many other Digimon, it doesn't evolve from or evolve into anything quite like it, but its family tree is far from bleak; it can evolve from the vaguely Rat-Fink like Chuumon according to the card game, and in one of the video games, it can evolve into the cool-looking Datamon, a computer virus Digimon. Datamon, in turn has been known to evolve into my second favorite Digimon, Parasimon, which is a parasitic eyeball bug tentacle monster. That's is most of my favorite things right there.
Sadly, I've seen a plastic figure of Raremon only once in my life, and its head was broken off. This sighting was made back when Digimon first came out in the 90's, too, so a simple little plastic heap-monster has eluded me for at least thirteen years. Doesn't anybody out there have one hanging around? I could draw you a piture for it!