Pro Freeflow combat pioneer
Arkham Asylum is the first game to bring us freeflow brawler melee combat in its full glory. It invented the combat genre where you fight a multitude of enemies who take turns attacking you, while the player has a basic attack, a parry+counter and a combat roll. Getting multiple hits in on enemies builds up a combo streak that makes batman stronger. This streak is reset by getting hit by an enemy. Other games, like Assassin's Creed, had superficially similar combat systems, but not as optimized as this and they did not feature hit/combo streaks. Arkham Asylum's freeflow combat system is very suitable to be played with controllers.
Pro Fun stealth & gadgets
Remaining stealthy and getting stealth takedowns is important in Arkham Asylum's gameplay. Arkham Asylum gives the player a relatively large number of different gadgets to use for different combat purposes, such as ranged takedowns, cutting ropes, diverting enemies' attention, blasting through doors, traversing longer distances and hacking.