This is an image dump from the game "Pandemonium Classic Unity Edition" made by TL. The images were made with 3d Custom Girl. It recently hit 1.0, so these are all the transformations that are going to be in the game outside of mods.
Basically you play in a transformation/corruption sandbox trying to survive long enough to escape. If you do get transformed you hunt down the others which is a nice touch. The sandbox is also heavily customizable so you can make your own fun. It has a lot of transformation sequences so I figured it belonged here. It's a fun game that I recommend playing.
@MitchellTF all the transformation text strings are in the source code. It's organized per Monster as I recall.
@chakari sadly some of the images had to be graphically edited to look right so no. They did make a big archive of all the 3dcg mods used to make the characters though.