"A fantasy d20-themed dungeon crawler", to quote DarkGod's comment. Inspired by Incursion by Julian Mensch. Made available under Open Game License. This is a non-profit fan project. No money is made. There are currently only two people working on the mod. However, we have released several beta versions so far.
Beta 7 was only a week ago and we're progressing still. Among other news, the AI is getting smarter - or should we say "closer to Incursion's level". Humanoid monsters can now pick up stuff from the floor, avoiding that which is completely useless to them (like money and corpses).