The AI follows simple rules to determine which card to play. Both Blue and Red have the exact same AI. This means that with the same cards in hand and the same card on the discard pile, the AI would always play the exact same card. It first looks for Skip or Reverse cards. If there are none playable, it looks for cards of the same color, then for cards of the same shape/value (e.g., 1 on 1 or +2 on +2). If none of those options are available, it plays a +4 or chooses a color.

The increased difficulty currently lies in the fact that the probability of Blue getting a special card becomes lower while Red's probability increases. This means that gradually, you are more frequently forced to give Red a better card (since the available choices consist mostly of good cards), requiring more tactics.

This is a simplified explanation of how it works, but it's roughly accurate. I hope you enjoyed playing the game :)

I'm glad to hear that.

I agree as well :)

Thank you very much. I'm glad you enjoyed it.