Thaddeus
Thaddeus was one of a pair of Metathran commanders created by Urza to lead the Dominarian armies during the Phyrexian Invasion. He was the twin of Agnate and the two shared a semi-telepathic bond, which helped coordinate their armies on the battlefield.
During the battle of Koilos, Thaddeus's bond with Agnate was intercepted/interrupted by Tsabo Tavoc, who crafted a plan to lure him into her trap. While Agnate's division of the Metathran army became mired in battle, making little progress towards the Caves of Koilos, Thaddeus was able to easily cut a path through the Phyrexians to the Caves, wherein he was was captured and then experimented upon by Tsabo Tavoc. Her cutting and probing into his body confirmed for Thaddeus what he had already begun to suspect--that the Metathran and Phyrexians were more alike than different, the main difference simply being that they had been created by different masters. At the end of the battle, Thaddeus was found by Agnate, who had to deliver a coup-de-grace to Thaddeus to end his suffering.
Thaddeus was replaced by Eladamri as the commander of the other half of the Metathran army during the Battle of Koilos.
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