Doubleface

Sideways (or in Japanese version: Doubleface in Micron Legend; Noisemaze in Galaxy Force) is the consummate con-artist. He is misleading and deceitful in everything he does, and he lives for the look of shock and betrayal on his victims’ faces when they realize he’s played them for fools. When the displaced population of Planet X allied themselves with Unicron to avenge themselves on Gigalonia (Gigantion in English version), this treacherous nature made him the perfect robot to pull off the ultimate act of treason - an attempt to sow confusion between Cybertrons (Autobots in English version) and Destrons (Decepticons in English version) to prevent them from uniting to oppose his dark master. No one is quite sure what he actually is.

(Source: Transformers Wiki, edited)