8 net maps. These are split between a few standard (pretty nice, in most cases) arena maps, and several team-oriented game maps. There's a capture-the-flag variation (already released), a mortar-style combat map, a pretty slick KOH level, and more. Construction is good, ammo is plentiful, and for bigger groups, the team play should liven up your carnage-fests.
Another type of capture the flag. Find the switch in your opponent's base, then come back and flip your own. Your opponent's base will fill with lava. (Likewise, if he gets to yours first, upon flipping his, your base will fill with lava... should make you think twice before flipping...)