A really cool concept! It's an interesting puzzle to try and position your faces in the right way!
I never quite figured out how the "Attack" face worked... I would land next to an enemy, with the Attack face up, yet I didn't attack them? In general I feel like there should be a bit more breathing room when you either get a kill or get killed - there are times where I killed an enemy without knowing how I did it, or times where I got killed even though I thought I was moving into a Defense position.
The only face I figured out was the Ranged Attack face - you shoot in the direction you moved. However, I'm sure the rules for the Attack & Defense faces are just as simple, I just couldn't figure out those rules because I couldn't see what I was doing wrong or right.
I love how expressive all the characters are!