NWN2 and copyright question?

Hi, new user here. I have made a NWN2 mod that has only one map where you defend against different invaders. You choose who you want to defend against by “inserting 20gp to play”. What I need to know is, if I offer invasion waves based on the games listed on this site, what, if any, copyright am I violating?

And no, no one makes any money out of this.
No matter how hard I try, creature appearances are not going to be any where near similar, but can I reference the name of the game, and the characters in a free downloadable mod?

You’re not gonna get C&Ded for a small NWN mod.

But the CEP was ordered to remove all Dungeon Siege based community made models. So I’m just asking for others thoughts.

If you get served a C&D all you have to do is not show people what you’re doing.
Honestly the worst they can do is tell you to stop and then you’ll just make it anyway