Apparently the artist for the original Slave Zero envisioned a world of biomecha more horrible than Evangelion, especially the protagonist, but the suits at Infogrames throught the art was too scary so they had them tone it all down and give the protagonist biomech a friendly face so it ended up looking like The Iron Giant's inbred cousin:
Years later Ziggurat bought the rights and went about making a prequel that takes the original biopunk nightmare art and dials it to 11. From food carts in the background selling slices cut from unidentifiable meat things to Gigeresque architecture that's just a little bit redder and fleshier, to skittering face monster that wouldn't look out of place in The Thing.
I'm having an absolute blast so far.
Also the protagonist is very, very gay. Makes Alucard look positively butch.