By the time of Transformers: Energon, Tidal Wave and numerous other Decepticons had allied with the Autobots. Possessing a new green and white paint job, he was the guardian of the Asteroid City Energon mine, until it was attacked by the Terrorcons. He was brought to Scorponok and Alpha Q, and was persuaded to join them under the false pretense that they were working to resurrect Megatron. However, this would prove to be a mistake, and Megatron returned to life on his own, and earned Tidal Wave's loyalty, as well as that of Cyclonus and Demolishor – both of them Megatron's minions and Tidal Wave's comrades in Armada. During the attack on the Desert City Energon mine, Tidal Wave mistakenly grabbed an Energon star, resulting in lightning-like burns covering his entire body.
Tidal Wave would continue to serve Megatron throughout the series. When the unruly and traitorous Shockblast joined the group, Tidal Wave voiced displeasure, as though he and Shockblast had some sort of unclarified history. In battle, Tidal Wave was heavily damaged as a result of Shockblast's recklessness, and thus, he was reformatted by Megatron into Mirage. He now had a smaller, sleeker, speed-boat form, a sharp contrast to his previous form.
Mirage remained on Megatron's side until the end. This devotion would carry on to the end of the series, where Mirage flew into the Energon sun that had resulted in his leader's demise, all out of a feeling of extreme loyalty to his master (along with what appeared to be a romantic infatuation with the Decepticon leader)- making him a tragic example for those who swore all-encompassing loyalty to Megatron.
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