Example of a simple game updated from The Game Maker's Apprentice chapter2 source code to work in Gamemaker:Studio.
You play a mother dragon who must rescue her hatchlings from an unpleasant band of demons that have kidnapped them. The band’s boss sends a stream of demons to destroy the dragon as the hatchlings make their escape. The mother can fend off the boss’s minions by shooting fireballs, but must be careful not to accidentally shoot the hatchlings! The arrow keys will move the dragon up and down and the spacebar will shoot fireballs. The player will gain points for shooting demons and rescuing young dragons, but will lose points for any hatchlings that accidentally get shot. The game is over if the dragon is hit by a demon, and a high-score table will be displayed.