A customized machine based on the STH-05 Hyakuren sold by Teiwaz, its armor is lightened for operating under gravity. Unlike the Hyakuren which is for anti-mobile suit battle, the Triaina specializes in using its overwhelming combat ability to assassinate VIPs using hit-and-run tactics. Its sensors were enhanced, and in terms of weapons, it carries two folding knives in its shoulder armor, and can use an assault rifle as its ranged weaponry.

The Triaina appeared in Avalanche colony to assassinate Ted Morugaton, but was defeated by Argi Mirage in his ASW-G-29 Gundam Astaroth. The pilot then committed suicide to erase any potential evidence of the assassination.