Make a game something like
.
You have to collect gremlins, with this you can put them in chest to get the letters B, A, T. After collecting all, you get a bat, and you can only punch the penguins. Power orbs are coming out of penguins and you need to collect them to level up the bat, after that you can kill the penguins. If too much penguins mutate and go to the doom scale, then you lose.