From Halopedia, the Halo wiki
In March 2553 he was working in the fields with Sensen and Gikak when they encountered Evan Phillips, who had translocated in the nearby Forerunner ruins via a portal. He thought smoke in the distance meant humans were invading, and was disappointed to find out otherwise. After a brief conversation, they agreed to accompany Evan to their lords Keep, on the way they were attacked by Banshees, one of which killed Sensen, which upset Dengo very much. Evan managed to calm Dengo and Gikak down and continued on to the keep.
Dengo was known to take Infusion as it helped pass the time working out in the fields.
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