Captain Marshall, or John Marshall, is one of the 54 Collector Cards in RAGE to be played in the minigame Rage Frenzy.
Location[]
The card is found in the Authority Prison during the quest "Liberate Captain Marshall". There is a locked door near the cell block where John Marshall was. The player should use a Lock Grinder to break it open and get the card and some goodies. Marshall will wait for them while they're looting the room.