Mimic's battle with Namor in the pages of Exiles was so brutal that the former X-Man swore to never kill again. The reality-hopping Exiles' mission of traveling to parallel worlds took them to a world where Atlantis had declared war on humanity, beginning with the invasion of Latveria. Although the Exiles do not trust their temporary alliance with Doctor Doom, Mimic not only ends up halting the invasion but getting into a brutal confrontation with the Emperor of the Deep himself, Namor. Namor's words combined with the disgust over the evil he and the Exiles have repeatedly faced gets Mimic, also known as Calvin Rankin, so angry, he literally beats Namor to death amidst a fiery inferno.
In Exiles #15-16, Namor and his Atlantean forces have invaded Latveria, deposing Victor von Doom while also commandeering his advanced technology for his own purposes. He plans to use a machine that will convert the atmosphere that will make it habitable for Atlanteans but toxic for the rest of humanity. With some assistance from the ever-arrogant Doctor Doom, Mimic travels to Castle Doom where he learns that Namor has also reprogrammed a small army of Doombots which Calvin destroys. Shortly after he's finished, he is challenged by Namor, displeased at the mutant superhero's interference with his plans.
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In the story by Judd Winick and Mike McKone, Namor and Mimic fight while the former Prince of Atlantis ignores Calvin's pleas to stop, believing war and the subsequent death of humanity beginning with the Latverians is the only logical outcome. When diplomacy fails, Calvin returns to Castle Doom and locates the machine, using his optic blasts to destroy it
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