The RX-178 Gundam Mk-II are three prototype mobile suits developed by the Titans, an elite special unit of the Earth Federation forces, in UC 0087. These are the first Gundam units seen in Mobile Suit Zeta Gundam. Based on the original RX-78 Gundam, the Mk. II is bound for success because of its incredible maneuverability, despite its obsolete armor materials. The Titans color scheme is replaced by the AEUG in favor of the traditional white and blue, to make it look less sinister.