Okay, that clears things up a bit for me. Press U and then choose a direction where you want to kill.
And the space trick to skip a turn I didn't realize!
I think I am prime example of how big walls of text get skipped. I think you're right, you did put those instructions somewhere, I just skipped through it, cause I wanted to play the game haha. I think button prompt icons on the screen with a short text would work for even the laziest and most impatient of us. So when I walk up to the enemy a prompt would appear "Press U to swing sword", then "Press direction in which you want to kill". That's only in the tutorial level.