From Halopedia, the Halo wiki
During the Battle for Earth, his squad was dispatched from the UNSC In Amber Clad to relieve the ground forces. Their D77-TC Pelican was shot down over Old Mombasa by a Type-47A Scarab walker. He survived the crash, but his squad was soon attacked by a Covenant patrol. He was nearly killed by a Kig-Yar Sniper, but Butkus managed to just avoid the shot. A Special Operations Sangheili then tried to sneak up on him with a Type-1 energy sword. Butkus' rifle was destroyed and he himself narrowly dodged the attack and fell to the ground, picking up a Type-25 plasma pistol and charging it. As the Sangheili took Fones hostage, Butkus was able to shoot the Sangheili and save his squadmate. His squad then met up with John-117 and helped him to chase down and destroy the Scarab.
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