Great concept, a fun twist on snake. The voicelines are hilarious!
I feel like it could use some more refinement, like removing the ability to turn into a wall, which causes you to lose the game if you try to turn a little too soon; maybe only make the king fall if he gets stuck, or crashes into a follower? Changes like this would enable the player to take their time and think about the puzzle. Unless you want this to also be about reflexes, and not just puzzling, which is actually completely fine (just for a different audience, maybe).
Anyway, this is a great entry!