This is Desdorago, the first monster to appear in modern times in Ultraman Trigger's universe. Dubbed as "Beginning Monster". He appears on earth 6 years before the awakening of Trigger. In his first appearance, one of the horns was broken.
Because of this event, Mitsukuni & Akito formed a connection. This event was also the reason for the creation of TPU & GUTS-SELECT.
A new scan from Ultraman Trigger & Ultraman Z's crossover episode.