This mod fixes the issue where Player 2 is ignored by DYOM actors, this is of course because DYOM wasn't built with 2 players in mind.
However, with this mod, DYOM enemies will now shoot at player 2 just like player 1, it is extremely easy to simple to install, and it is automatically enabled upon launching DYOM.
Works in DYOM 8.1 and DYOM 8.3 Alpha 10, I haven't tested other versions, but they should work fine too.

How to install:
Drag and drop "2P DYOM Fix.cs" into your cleo folder.