What bug can cause zero score?

I had this problem about one years ago and I fixed it by finding an infinite loop that doesn't use getXXX() or setXXX() methods. Another thing I did was rewriting everything again starting from the last version.

Thanks for sharing! Do you mean an infinte loop will disable your bot for every round? It seems that infinite loop will cause the system console print something like (xxx not stopping, trying a force stop), e.g. Krabby is printing 35 of that messages per pairing on my machine. So that should only affect one round by it self. Anyway, I’m not receiving that message on the broken battles.

Yes, I mean that but if you don't call the XXX methods, the program doesn't throw an exception. It causes the bot to get stuck and stop updating itself or sometimes it disables the bot.