There are quite a lot of side missions players can play to break up the story segments of the game. Even better is that they are still accessible when the main story is completed.
This game's predecessor pioneered a new kind of free-flow combat system that's intuitive, highly responsive and supplemented with power-ups, combos and ability to use gadgets to add variety and depth.
Arkham Knight has the open world aspect of the previous game but has now introduced the Batmobile for use on the street with a full weapon loadout. Being able to drive around thee streets of Gotham as well as use the vehicle to take down bad guys makes for an exciting experience not seen in the series before.
Possibly the first release (certainly the first AAA release) to be digitally withdrawn from sale. Buyers were refunded.
It was reinstated months later, but the port was not much better and still had terrible performance issues.