Snake Game

The original grid snake, unchanged and still a genuinely good puzzle. You move on a grid, eating makes you longer, and the only way to lose is to run into a wall or into yourself — which means the game gets harder purely as a consequence of succeeding at it. That self-inflicted difficulty is the whole design and it is why the game has outlasted everything it was released alongside. Beyond a certain length, survival requires planning a route that leaves an exit rather than taking the direct path to the next apple, and experienced players spiral deliberately, keeping the body in a shape that can always be escaped from. That technique is the difference between a score of forty and a score of two hundred. There is nothing else to it: no upgrades, no modes, no progression beyond the number. Rounds last a few minutes and restarting is immediate. It plays with four inputs or swipes, runs on anything including very old devices, and is suitable for children while still being a real puzzle for anybody willing to think about routing. Complete, and not improvable.