I just thought about this and was wondering.

For right now, it will probably be singleplayer unless we have a lot of people interested in doing co-op. My thing with that is that it only makes the boss more trivial but we can wait and see. If you like, you can try a co-op run and see how it goes. As it stands for right now, it will be singleplayer. Thank you for asking though, I kind of forgot about that :}