The singleplayer wasn't the most-focused-on thing on Blockhead 2D, but I made some minor changes to the CPU in the training including:

*There's now absolutely NO chance that the CPUs will pass through objects.

*Jack will trick you in the corners, now and maneuver himself so he jumps on you instead of him.

*Fixed Jack's collisions so that we won't hit you by "jumping down" into your collision boxes.

That's pretty much it! Have fun and enjoy the game, as usual! :D