From Halopedia, the Halo wiki
Tesh was an elderly human male who served as the engineer aboard the modified Mariner-class transport ship, Ace of Spades. He, Captain Rion Forge, and Cade were the original three members of the ship's crew. After joining up in 2555, Niko often enjoyed giving Tesh a hard time and in turn, he made empty threats toward Niko. Niko thought of him as surly and old. Tesh's position as the Ace of Spades engineer was filled by Kip Silas in January of 2557.
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