Stick Around
From Halopedia, the Halo wiki
Stick Around
Stick Around is an achievement in Halo Infinite. It is unlocked by killing Tremonius with the Skewer. This achievement awards the player 20 Gamerscore.
Walkthrough
Near the end of the level, a Jiralhanae Sniper equipped with a Skewer can be found alone in a room, where he is guarding the Power seed needed to activate a Gravity lift. When fighting Tremonius, using energy weapons to quickly drain his shields before dealing the finishing blow with a Skewer is recommended.