http://www.forgehub.com/forum/reach-gametypes/110275-outlast.html
on
GROTTO

ABOUT
Grotto is a map specially made for the Outlast gametype. (If you don't understand how it works, please visit that topic.) It features a poorly-lit cramped cave area that the Survivors must defend from the Infected horde for as long as possible. I made Grotto for slightly smaller parties, and for hectic, frightening, close-quarters combat. There are three entrances for the Infected to get in. The weapons available for purchase on Grotto are the Assault Rifle, the Magnum, and the Shotgun. There is one Grenade Spawn as well.

PHOTOS
Action shots coming soon.

Interested in making an Outlast map? Post it here, and I'll add it to my Outlast File Set.