The title given to the supreme leader of the Decepticons or Predacons. Mainly used in Japanese G1 Transformers series, the only use of the term Emperor of Destruction in the US was in the series Transformers Prime.
Devil Z/Devil Zarak (Scorponok fused with Devil Z)
Galvatron (Beast Wars II)
Starscream (Self-Proclaimed, and later referred to as Lord Starscrean, Emperor of Destruction in the Transformers Prime movie)