Drakengard is a series of action role-playing games in which the player controls a dragon rider and performs a number of missions both in an on-foot hack and slash style and in aerial combat.
The world of Drakengard is protected by seals that prevent it from falling into ruin. Any person or creature can become a seal but the burden is heavy. The fewer the seals the greater the burden grows which may become great enough to drive one into insanity. The various mystical creatures of the world can grant special powers or abilities to humans through "pacts". A human and creature who enter a pact combine their souls into one and the human must surrender something of theirs. The human will not know what they’ll loose until the pact has been made but it can range from their voice, sight, womb (ability to conceive), artistical/musical talent, or ability to feel a certain emotion such as joy.
Nier takes place within an alternate realm in the Drakengard world, exploring and expanding upon the endings in the previous Drakengard games.