|First appearance||Transformers: Exodus|
HYDRAU! HYDRAU! HYDRAU! went the chant among the crowds. An illegal gladiator who battled in the hidden gladiatorial arena beneath Iacon itself, Hydrau was a creaking cast-off of some industrial enterprise. He wore his own name painted across the backs of his shoulders.
The crowds chanted his name when Megatron revealed to Orion Pax the violent, illegal sport festering in the heart of Iacon.
He won a match against a numberless horde of Minicons. Sadly, his combat partner was not so lucky, dying in the match. As the crowd celebrated, Megatron commented, with a smile, that he might have found some competition. Orion did not believe it for a moment.