These are my two surviving Marathon Evil maps.  Secret Agent Man is a multiplayer map.  It's pretty fun, especially with the extreme darkness, and, if you're smart or just lucky, you may find the secret area in the map.  The main reason I love this map so much is that it was the first map I made with some serious monster pathing.  If you play with monsters on you'll notice that they'll follow  you like mad.  U.E.S.C. Doom was an idea I had for a single player/co-op scenario.  Basically, you're a prisoner who has to escape the clutches of BOBs, and lots of them.  Remember though, the S'pht are your friends.  Basically the whole objective of this map was to get into the captain's quaters, grab a key from his bathroom, use it to get into the engine room, take a teleporter to the shuttle bay and escape.  Well, i never quite had the nerve or inspiration to make it necessary to get the key or to make the scenario end when you enter the shuttle.  But, i've found it to be quite fun.  Ammo is very limited though, so don't kill each other or waste the ammo.