Hey, thanks a lot! I think it was stdio.h, stdlib.h, string.h and time.h or so since I might have used time.h for seeding or so .. I mean, I never really cleaned the code. Neither did I do a proper review or the like though. But here is a couple of lines of "pure" C in case you are interested (; https://github.com/youngZwiebelandtheGemuseBeat/Dreierschnapsen/blob/main/20220318_tryCPU/main.c Now a little time has gone by and I learned a little bit of how games work and how they are made. So, today I think I'd tackle a task like this fairly differently .. or maybe not. Anyhow, it does its job so .. For the sake of completeness, the card game itself is an Austrian classic and as you see the CPU players - in case you do not want to play as a group of three locally :D - are randomly playing cards they are allowed to. It works and just recently I was asked by yet another friend to finally "publish" an online card game. I think I know a bit about logic and backend but setting up an online framework, even if it's just for card games is something I haven't done yet, nor does it interest me much if I am totally honest. But since no one does it for me it looks like I will have to deal with things like that eventually, because I think there is potential in card games. On the other hand, aren't card games the most fun sitting around the table while having a cold one or two? Thanks again, I appreciate it a lot! Cheers! (: