APACHE

Profile: A somewhat eccentric, senile and highly emotional character, Apache often seems like he's on the verge of a nervous breakdown. As second in command, he tries to keep the other Cybertrons in line. 

On Sabretron, Apache and Lio Convoy (then known simply as Convoy) were once slaves of the Destrons. The slaves were often overworked, and once Apache was on the verge of Energon starvation, however, Lio Convoy saved his life with an Energon transfusion. Since then, he has sworn a life debt with Lio Convoy and has served him loyally.

As luck would have it, Apache is prone to getting into trouble and often it's Lio Convoy who has to pull his servos out of the fire. It was Lio Convoy who sacrificed himself during the Destron ambush in the asteroid field which sent Lio Convoy to Gaea. Apache feels a tremendous amount of guilt each time Lio Convoy saves his life. Often he tells his leader to abandon him and save himself, but of course, Lio Convoy would never abandon a comrade.

Lio Convoy and Apache were the first Cybertrons to encounter the Insectrons. During Lio Convoy's battle with the Insectron leader, Mantis, Lio Convoy fell under Mantis' hypnotic spell and was about to be sliced apart, but Apache saved him by transforming into his Mode 3 berserker fortress mode.
In this mode, Apache is full of berserker rage and is practically indominable. Unfortunately, it is an involuntary action which he cannot summon at will. Also, he has no memory of what he does when he transforms into a berserker.