Because this game was delisted from digital storefronts around 2012, it is often classified as "abandonware". The Keygen Need

: If you are prompted for a code on Steam, usually launching the game a second time or checking the "Manage" > "CD Keys" section in your Steam library resolves the link between the two platforms. Security Warning

If you were interested in the 2009 game, the 2009 version is no longer available for digital purchase, but the safest way to experience it would be to find a legitimate used physical PC or console copy from a reputable seller.

Thankfully, there are many legitimate ways to play both classic and new Avatar games that are safe and often very affordable.