Key mode is a game mode of the Google Snake Game. It is where the player has to eat a gold shape to make the food appear. There is also a dark green square with an outline of the gold shape in it. This is where the actual food appears. These dark squares act as walls, too. You lose if you run into them. Key blocks are not able to spawn 1 tile away from the corner.
It's possible to get soft locked while playing with 3 apples, 5 apples or dice, by having the key blocks seal away the keys in a corner.
