The Unas were a group of Zoanoids specially developed by Luggnagg de Krumeggnic and his fellow rogue Zoalords. Their primary purpose was to counter the threat of Zeus' Thunderbolt's own brand of Hyper-Zoanoids, the Libertus. After discovering Sho Fukamachi's friends' hideout, the Unas - led by Richard Guyot - attacked, interrupting a confrontation between Sho and Agito. Individually, the Unas were no match for the Guyvers or the Libertus, but they possessed the ability to combine together into larger, stronger forms. By Guyot's command, two of his Unas merged into "Dimer configuration", three into "Trime configuration" and four of them combined around Guyot himself into "Quadriga", a giant, spider-like monstrosity which acted as a chariot for the Zoalord!
Dimer, Trima and Quadriga proved incredibly succesful in combat, dealing the Libertus their first defeat, and a completely decisive defeat at that - two Libertus failed to even damage the armor of the Dimer.
It is as yet unknown what the limits of this combining effect are; it is however clear that the combining geometrically increases the power of the Zoanoids - Dimer was more than twice as powerful as a single Unas. Also unknown is whether the configurations are standard per number of participating Zoanoids; Dimer was taller and bulkier than an Unas, and possessed two arms and two pairs of legs, while Trima had six arms and only two, but very massive legs; and Quadriga, of course, is not humanoid at all.