Words cannot describe the excellence that is Batman : AA. The definitive Superhero game.
From the start, you can already sense the tension as Batman walks Joker to his cell in Arkham, and the game eases you in with tutorials on the basics controls of fights & combos. Not only that a variety of missions from the get go lets you experience the multiple facets of being Batman. This brings up Detective Mode which opens up a whole lot of puzzle & strategic opportunities.
In Detective mode, you can plan how to approach your enemies, and this is easily the best feature of the game, which is how do Batman goes about taking down the goons. At your disposal is an array of Batarangs, Batclaws, Explosive Gels, and good-old fashion punches / kicks to bring the baddies down. This also leads to the Predator Challenges and you can play this challenges even after you completed the game to amass more trophies.
As Batman is also a master detective, this mode is also used to hunt for clues. Although pretty undeveloped (since its a basic search and follow the trail in this mode), it does balance out the combat portion of the game. Perhaps its because Batman : AA its such a magnificent game already, much much more is wanted.
Go get it now if you don't have it already.