I was playing with two other people and the AI would sometimes finish earlier that us taking away all the fun. Since I wanted to unlock new maps and have fun while doing it I just added a 4th player and left it standing there.
No problem, thanks for replying. I also have one more thing to mention. I sent you a message over on Twitter because I noticed a typo in the speech bubble that appears before selecting the tutorial 2. More precisely it's written "After that you'll can fight(...)".