Tardyon
タージオン
One of the seven (nine in the manga) Mu that were naturally born on Naska. He is brothers with Tachyon (in the anime series). His name comes from the name for particles that are always slower than the speed of light.
In the fight against Keith and the Terran forces, he and Cobb are both killed. In the manga it is mentioned that he is wounded and you see him in occasional panels.