tip: if you want to beat last boss easy just stay in one of the top corners and head shot him with bow. make sure you jump cause he tries to head shot you. I used bows all game so head shot was kinda easy for me at end.
speed 8 moves goes off at same time as speed 7 moves. really needs system where switching card sticks with same energy as exit or it regains 20 energy every turn it's out. not have a card have 0 energy and switches then comes back when cooldown is off to have 100%.