This achievement will unlock upon finishing the first level, which is a tutorial of the game. At the end you'll fight a dragon. All of his attacks can be avoided by standing behind one of the two shields except the attack where he shoots fireballs into the air. Simply run to one side to avoid them. When he isn't attacking, shoot arrows at the red plate on his chest to damage him. After enough damage he'll die. You'll then be sliding down a building and will have to perform a very simple QTE. Upon making it to the end, you'll wake up and unlock this achievement.