Abuse was made by Crack.Com which was formed by Dave Taylor of ID. I don't know if any other ID guy was involved. It was written in some weird language if I remember right. Also the company I think had six employees, but the game didn't sell very well, or didn't sell well enough to supprot six employees at least and they ended up closing up shop while in the middle of production of their second game, which was a 3D tank game called Golgotha. The Abuse engine I think they released the source to, but you weren't allowed to use it in commercial projects because of contractual obligations they had. I don't know if that has changed, but it would be silly to try to use a DOS based game engine these days, and the game's lighting system would be trivial to do with 3D acceleration nowadays.