Here’s some things I did.
A sketchy Necro.
http://img246.imageshack.us/img246/1317/sketchynecrobyphobosrombp6.jpg
All of Necro’s colors
http://img215.imageshack.us/img215/5741/necrocollagebyphobosromxw0.jpg
Mario’s Gang
http://img226.imageshack.us/img226/6443/mariosgangbyphobosromulxf1.jpg
Merciless Marine from the bungie game Marathon. Marathon was the predescessor to Halo.
http://img178.imageshack.us/img178/6069/mercilessmarinebyphobosjj0.jpg
The Terminator
http://img153.imageshack.us/img153/7775/futurewarbyphobosromuluos3.jpg
Original concept: Morpheus Subway Station.
http://img175.imageshack.us/img175/5638/morpheussubwaystation2beo7.jpg