Answer: A Slot Machine
In the hit Super Nintendo game Star Fox, there was a super-secret level (Out of This Dimension) that required shooting and destroying a massive asteroid, then ramming the bird-like origami creature that emerged from it, which would then teleport you into a bizarro land pocket of space where you had to face off against a slot machine, the type of automated gambling machine found in casinos across the world. Using the blasters on your spacecraft, you had to pelt the arm of the slot machine, “pulling” the lever over and over again until you eventually racked up three 7s in a row (other combinations gave you little to nothing at best or, at worst, caused the machine to shoot missiles at you).
What did you get when you eventually beat the machine? You unlocked a mini-game where you could shoot at floating letters and make them spell “The End”. Upon successfully lining them up, they reset and you had to do it all over again, making the mini-game found in the depths of the alternate dimension behind the bizarre slot machine a game that never truly ended.