Batman: Arkham Knight is an open-world action-adventure game, where you play as Batman and have to hunt down Gotham's most dangerous criminals. It's the fourth game in the main series.
Pro A pretty great story
Takes inspiration from so many areas of past Batman lore and creates a more interesting interpretation of a classic story. There's some pacing issues occasionally and it goes on a little too long at points, but is more than redeemed by a compelling overall plot, excellent voice acting, and interesting characters.
Pro Ability to drive around the Batmobile
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. It's fast, beautiful, controls well, and converts into a tank for some combat missions that are almost as fun as the standard hand-to-hand combat. The moment when you rocket off a ramp and shoot a hundred feet into the air out of the driver's seat into a glide over skyscrapers... it's great.
Pro Excellent free-flow combat system
Batman: Arkham Knight still uses the combat system pioneered in the very first Arkham game, but with various improvements. It is intuitive, highly responsive and supplemented with power-ups, combos and ability to use gadgets to add variety and depth.
Con Lackluster, short DLC story missions
Don't buy the season pass unless you can find it on sale. It's not bad, but not worth an extra $20, and certainly not the $40 it cost before price drop. (FYI, you get a complete experience without the DLC - it truly is extra content, not main game content cut out and repackaged.)
Con Detective Mode investigation segments and the like are still boring and not good
Sometimes to push the plot forward the game will force you to do some "investigating," which basically comes down to a stupidly easy 'Where's Waldo?' minigame. It's not bad, but it doesn't really add much to the experience and feels kinda like a waste of time.