The folks GameMaker Studio have just updated their software to version 1.2.1214, and to celebrate they’re allowing users to upgrade to the Standard Edition of the program for free.
To be eligible for the upgrade, users must first install the most recent version of GameMaker from the official site. From there, users have to register to get a key sent to their email. Once redeemed, the Standard Edition of GameMaker is unlocked.
Unfortunately, this upgrade is not available through Steam.
GameMaker Studio is a program that has recently been used for some very successful indie games, including Hotline Miami and Gunpoint.