THE Chips Dubbo?

From Halopedia, the Halo wiki

THE Chips Dubbo? is an achievement in Halo: The Master Chief Collection. It is unlocked by fighting alongside Chips Dubbo and listens to his stories in Halo 2. The achievement is worth 5 Gamerscore and can be unlocked on any difficulty. It can be obtained as early as Cairo Station and Outskirts.