Vavel itself has one in midway through the game when it rebels against the Genesis system trying to enact the aim of making Vavel rampage and kill three billion people. Rewriting its own programming, Vavel pulls the plug on the Genesis System. Vavel then promptly reactivates it to use its power and with the chairman's help utterly curbstomping the Centurion attacking the city.
The chairman and the Meganite share one in the game's final battle. The Volgara have unleashed their strongest yet, and Mission Control informs you the battle is utterly hopeless, that this Volgara outmatches your Meganite in every way. A human and a meganite together on the other hand are able to slay the Volgara's final champion.
The chairman gets one in what is a very frustrating mission for the player. Gllang's transformation system malfunction, leaving it stuck in tank mode. This leaves the player with a limited amount of energy to attack with, after which they are stuck fighting the Volgara on foot with grenades. Protagonist wins.
Souya gets one near the end of the game. The chairman is busy elsewhere and a multinational task force is struggling against a group of Volgara. Souya's own Meganite Valdor arrives on the battlefield, and in mere minutes has destroyed seven of them. It's likely that most of those Volgara were at least damaged by the task force, but it's still a phenomenal feat.