Here is the full list of all 12 Dragon's Lair achievements.
Complete the game on Arcade Mode
Get off on the elevator on the last floor.
Never make a correct move in a new game.
Play Dragon's Lair on its Anniversary: June 19
Complete the game on any mode.
Lose your last life in the Drink Me scene... Watch Carefully!
Complete the game with the move guide turned off.
Complete the game in Hard mode.
Complete the game without dying.
Get the highest possible score (427,469).
Use the shortcut in the Giddy Goons room.
Dirk dies via asphyxiation in the bedroom scene.