Board Thread:Warhammer 40k General Discussion/@comment-10051320-20130526124353/@comment-3580035-20130527024258

It's rules are in Apocalypse Reload, and it can only be used in Apocalypse games or if your friends let you (which i don't see why they shouldn't as it is costed appropiately). Most competitive environments won't let you use it though as it's not in the normal Space Marine codex. The model itself is no longer sold and was limited edition. It is possible to convert one though (i think).

It can be used by any chapter, its just a rare relic in fluff. The name Terminus Ultra has no relation to Ultramarines.