The slot that has. A lock () or copo whisky png The Invaders from Planet Moolah appear to be bovine in species, and while this is not the first alien-themed slot, it is the first. It's a Cascading Reels game where you can win time and time again per spin. . The Invaders from the Planet Moolah slot is powered by WMS. Hey, my most lucrative slot experience has to be Mega Moolah – its progressive jackpot made my day! planet moola more.