Ah, my mistake. I thought it was from the late levels of redemption, but it must be bloodlines.

In redemption (MP) you choose a map and the host acts practically as DM, spawning enemies and loot as the other players crawl through the dungeons. It's overly complicated, but an interesting proposal.

There is a good chunk of items that you wouldnt normally find in the SP (weapons with special stats, weapons for humans) which makes me think that they had a bigger idea of how the MP should work.