Mutate

Mutates are a general term to describe vicious creatures that have existed across Mobius since before recorded history. The animals that make up this grouping can be derived from many species and while similar to their natural cousins, are so genetically altered that it would be hard to mistake them for anything else.

Origins
No one really knows exactly when or where the Mutates first began to appear on Mobius. Some speculate they came to be in the Days of Fury from long ago. This is a probable scenario given that the Xordas' Gene Bombs caused the Days of Fury as well as the mutations of the animal and human populations present millenia prior. Others like Nate Morgan have devoted some study of them and believe they are products of the forgotten wars from Mobius' less-distant past. In any case, it would appear they have been around long enough to earn the fear and respect from Mobians and Overlanders alike due to their violent natures and general aggressiveness. (StH: #65, #67, #124, #125, #148)

Bottom of the World
The first known record of Mutate sightings were when Nate Morgan traveled down to the Southern Tundra in self-exile. There, he encountered a yeti who had become the victim of an avalanche. Despite being dangerous, it was mortally wounded and seemed to cry out to Nate, pleading for help. A humanitarian at heart, Morgan could not leave it to perish in the harsh elements and aided it by replacing it's mangled limbs with cybernetic prosthetics. He earned the yeti's respect, whom he named Eddy, and in return made an invaluable companion who assisted him in building a home in the frozen wasteland. (StH: #65)

Appointed Guard?
At the end of his quest to defeat Ixis Naugus, Sonic the Hedgehog encountered a second Mutate while searching for the Ring of Acorns. The creature was found sleeping inside the Lost Temple of Shazamazon deep in the Great Rainforest. This time it was a giant serpent that became active after the Ring was taken and tried to eat Sonic. He only managed to avoid this fate by tricking the snake into tying itself up like he did to the late Dr. Ivo Robotnik's former creation E.V.E. (StH: #21, #67)

Eggman's Pet
A third Mutate was seen shortly after Nate Morgan was abducted from Mobotropolis by a number of war prisoners who had escaped from the Devil's Gulag. While Sonic and the Royal Secret Service fought to free Nate on Big Kahuna Island, a satellite in orbit above them was activated by Dr. Eggman. It then sent a signal which awoke a cyborg squid resting beneath the island which then broke through the surface and grabbed Snively and Bomb. Bomb exploded seconds later and was believed to have destroyed both the squid and Snively along with it. In reality, Eggman merely used it as a cover for Snively's transportation to his space station. (StH: #70)

Background

 * Assuming the snake was there when Nate Morgan took the Super Emerald originally found in the temple, that was twice it failed to protect a treasure. Although, how Nate would have gotten past the Mutate in the first place is anyone's guess.