NieR: Automata is an action RPG set several thousand years after the original NieR. Living machines from another world invaded Earth and the remnants of humanity fled to the moon. Since then have been sending android units back to Earth, to fight proxy wars against the machines, until it becomes safe to return. This game follows three units from the YoRHa android series: a battle unit named 2B, a recon unit named 9S, and an older prototype unit named A2.
Battles are fought in the overworld. The active character can use a variety of different attacks, and may use one of four different weapon classes. Weapons may be switched during combat to create combo attacks. The character also has a Pod, a flying robot that launches automatic ranged attacks and can use different types of programs. As robots, the main characters may install plug-in chips in order to grant buffs and other helpful attributes. A character may have a finite number of chips equipped at once as each one requires an amount of storage, but it is possible to save different configurations and switch on the fly.
RPG elements include various quests of which many are optional and an experience based leveling system where enemies generally level up to match the player's character level. Weapons and pods can be upgraded multiple times when the needed materials have been gathered. There are also various support items and shows where items can be sold and bought. Plug-in chips can be sold or fused for a price, making them stronger but often at the cost of additional storage.
Next to the main gameplay there are many flying shooter sections often involving 'bullet hell' environments. It is also often possible to hack opponents, which is presented as a different type of shooter mini-game. The game uses a story that is told over the course of several playthroughs, sometimes retelling moments but with another protagonist, or experiencing events before or after the main story. This leads to many different types of endings, including many joke endings where the game ends prematurely. There is no multiplayer, but network connectivity allows a character to retrieve items from fallen characters in the same area or revive the character as a temporary ally. A specific ending also involves network interactivity between players.
There is a save system along with a transporter to hop quickly between locations. Just like in the original NieR it is possible to ride animals as well to get around quickly. When a character dies, the body remains at that location along with a large selection of equipped plug-in chips. The player then has one chance to retrieve the body and the chips, because another death causes the body and the chips to vanish.