By all accounts this is a pretty rare GBA game.
From the auction:
So here’s the story here, this game is so rare most people don’t even think it was released here in the states. It was released in the EU as “Buster’s Bad Dream” and was slated to be released here in North America. Well the publishing company changed hands (this copy was released by Treasure Games), and all the copies were asked to be returned and the game was shelved. Even review copies were asked to be returned!
Wikipedia has a little more info with:
InÂ 2005, a US version of the game began popping up onÂ eBay and at small retailers, published by Treasure-regularÂ Conspiracy EntertainmentÂ as Tiny Toon Adventures: Scary Dreams. Aside from the title screens and legal information, it was virtually unchanged from the European version of the game. According to information on the box, copies of the game appear to have been produced in 2002 and shelved between then and the time it surfaced.
Cool item for a GBA collector.
Autographed by series head Koji Igarashi