JunkMetal

JunkMetal is a MMOFPSRPG developed by Metro and published by Enix in 2003.

It features a high degree of customization, allowing players to mix and match various parts and weapons for their robots, as well as different operating systems and software.

Also, it emphasizes PvP (player versus player) combat, where players can join one of two rival factions, POF or Infinity, or remain as freelancers.