The Titans Remnants are forces of the Titans that continued to operate after the Gryps War.
History
While not nearly as influential as the various movements that succeeded the Principality of Zeon following its defeat in the One Year War, the Titans Remnants remained a formidable force following the Titans defeat in the Battle of Gryps. The most notable of theses remnant groups would be the "New Desides", which would stage an uprising during the early stages of the First Neo Zeon War.
Even following this, they would be active in the early U.C. 0090s, with Titans Remnants utilizing the MRX-013-3 Psycho Gundam Mk-IV G-Doors against the forces of Londo Bell.