Thank you for your feedback, I will have to fix the night button. I wonder if this caused an error with the energy calculation. You should start off with 3 energy(cost is 1 or 2 depending on the card.) then it should increase your energy by the number of guests you have. Maybe the system tried to calculate the new energy but it didn't have anything to add so it got messed up. I'll have to test when I get home tonight.
Eventually I want to make more cards and allow the user to open packs to get more options in their decks. The rarer cards will cost more energy, I do think it's a little bit too much energy per cryptid at the moment though.
Thank you for playing!