Puzzle is a gray donkey who lives in the Lantern Waste. He is the neighbor and lone "friend" of Shift, the ape. Puzzle is a decent sort, but has gotten into the habit of letting Shift do all the thinking for him, even though he still has some glimmers of goodness every now and then.
One day in 2555 NT Puzzle and Shift were near the Cauldron Pool when they notice a lion skin in the water. Puzzle goes to retrieve it and Shift comes up with the idea that he disguise Puzzle in the skin as Aslan, and make everyone obey him. Puzzle doesn't want to go through with the deception initially, but Shift convinces him that it's the right thing to do.
Poor Puzzle is very miserable when he is made to stay in a stuffy stable and is barely let out for a breath of fresh air. There he remains until Jill happens upon him and frees him. He joins the group of Narnians, who hope that they will be able to prove the lies of the Calormens and Shift by having Puzzle as proof of a deception. This plan fails when the Narnians, so far deceived, refuse to accept Puzzle as proof. A battle ensues between the Narnians and Calormenes, which result in all the Narnians either being killed or thrown into the Stable.
Puzzle is later seen in Aslan's Country, finally rid of the lion's skin and looking the lovely and honest Donkey that he is. He is taken aside especially by Aslan, and is told something that makes him ashamed, but then elated.