From Halopedia, the Halo wiki
He is featured as a mini-boss in the Spartan-IVs' Warzone training simulations. The Marauder is a boss to appear on multiple maps in Warzone , and drives a Ghost. His Ghost cannot be boarded or hijacked. However, if the Ghost is flipped and unable to be unflipped, the Elite will leave the Ghost to fight with a storm rifle and grenades. His empty Ghost cannot be driven. Killing one will give the team 25 VP, and earn the player a Boss Takedown medal. Many regular Ghosts will also spawn at the same time, making it more difficult to kill the Marauder himself.
List of appearances