I found an interesting glitch; when you beat a level and get to the part where you choose another card, if you press shift+R before choosing a card it will not restart the last level, instead it will send you to the next level without either of the cards that you were supposed to choose. You can do that for both times you get to choose cards, so that means playing the game without beehive/warren or elk/adder, and also no cats for some reason. I don't expect you to fix this or anything, I just thought it was interesting, and it made it more challenging to beat the game.