Big Serow (Beastformer)

Big Serow (ビッグセロウ Bigguserō), also known by the nickname Sero (セロ), is White Leo's adjutant, a fierce but fair fighter and tactical specialist in the war against the Decepticon conquerors on planet Beast. He is the King of Saitan, the country (one of 38 on planet Beast) of his birth. Presumably this was his occupation before Alligatron's Decepticon-backed uprising sent White Leo's followers into hiding. He is specifically targeted by the evil Killer Fish for retribution over an injury Serow gave him years ago. He remains calm and collected no matter the situation, which greatly inspires the troops under his command to believe in victory, particularly Battle Bear who is at his strongest with Big Serow by his side.

Big Serow's MVP Weapon is the Big Boomerang, which can both cut through stuff and emit ultrasonic waves. Whether or not he has any relation to Little Serow is unknown.