press left or right arrow keys when in shop, press space when to place down a monster after buying it. Keep in mind you might have to add some stuff yourself like the limit for the shop monsters before they go off screen and turn invisible I'LL DRAW THE ISLAND SOON
Stuff I'll add later: A limit to scroll in market An exit button Decorations and structures Breeding Structure A better song system Multiple Islands "Sell" & "Move" buttons for monsters Better currency UI