The Monsters' Monster
Being the brief (picture-book) tale of three monsters who live in a castle
There they fight all day about who's the biggest monster. It starts with showing off and ends with actual fights.
One day they decide to fix this by making themselves a new monster: the biggest, baddest monster of all. Bringing it to life in the best Frankenstein's Monster tradition works just fine.
It's what happens immediately after that throws their plans awry.
A sweet little story.