From Creatures Wikia
A genome first developed for C2 to create a new type of Ettin more suited to life in the Swamp where C2 Ettins are usually found. It featured improved intelligence, longer lifespan and heightened sex drive. Swamp Ettins are also green and possess a tail. The C2 version is still hosted on some sites.
The C3 version follows the pattern established by the C2 design, with added homing instinct for the Jungle Terrarium and resistance to diseases found there.
The latest revision to it can be found on its creator's site, The Albia of Dr Washu.