The original Trine has been enhanced with its ‘Enchanted Edition’ which essentially reworks the game into the Trine 2 engine (making it look that much prettier and magical in the process). This will offer the original game, alongside Trine 2 multiplayer.
The Enchanted Edition is still in beta, but in the modern market, when has a game being unfinished prevented anyone from playing it? It is currently on Steam, and anyone who owns the original game can play it for free right now.
To play the game, right click on Trine in your library, and select properties. Select ‘Beta’ and enter TrineEEBeta2014. Trine: Enhanced Edition is then enabled as a new option for you to boot up in the game’s launcher.