When you’re not committing sororicide, Zero can complete side quests in Drakengard 3. Developer Access Games added these extra missions with missions such as collecting certain item drops from enemies within a set time or fetching items from treasure chests. Some of the side quests have restrictions like forcing Zero to only use her sword or a rule that prevents her from using items.
Some side quests act like a bonus stages where you fight waves of enemies and earn rewards depending on how many you takedown. Side quests are graded and the reward you get depends on how well you do.
Drakengard 3 is slated for release on December 19 in Japan. Square Enix announced they will bring the game to the West next year.