Description This is a modification for DOOM 3 that allows you to spawn allied Marines to help you with your hellish fight. You can spawn in sentry versions who guard an area, or follower versions that will follow you. There is also many choices for weapons each This is a modification for DOOM 3 that allows you to spawn allied Marines to help you with your hellish fight. You can spawn in sentry versions who guard an area, or follower versions that will follow you.