Gameplay is a combination of three modes: Investigative mode, Combat mode, and Stealth-hunter mode. Early on in the game, when the inmates aren't armed with guns, it looks like you can get by mostly with Combat mode. The controls haven't been 100% finalized, but it looks like you mash A and maybe Y to pull off punches, kicks and headlocks. There's also some button combo that leads to a slow motion elbow-drop, but I'm not sure what the demo runner did to bring that on. Right now, the game is still in pre-alpha, so they haven't hit their goal number of guys on screen for combat. I only saw up to five guys in a fight at once; but the demo guy said they had gotten the count up to 15. By launch, Rocksteady hopes to bump that to 20 so the Combat portion of the game will be even crazier.

During combat phases, a combo-counter appears in the upper left hand corner of the screen along with a health bar. The higher the combo number, the more XP Batman earns for the encounter. When you level up, you can upgrade weapons or fighting moves and the health bar regenerates automatically when the fight is over (unless you die, in which case - game over). They keyword here is "context." Almost all of Batman's moves are context sensitive. For example, you approach a grating over a vent and a prompt pops up, telling you to press A repeated to break the grate faster. You could do that, or you could hold down Right Trigger and then press A once to slowly and stealthily remove the grate and slide it to one side. This is the basis for the Stealth-hunter mode where Batman has to take out multiple minions without being spotted. So instead of running in a mashing A, you creep in and hold Right Trigger while pressing A to turn a headlock into a stealth-choke or a punch into a smothering move.

It all depends on what the situation is and that's where Investigative mode comes in. By toggling this mode, Batman sees the world in a sort of infrared view where everyone's skeletons are visible. You can see how many people are in an area, how many are armed, where possible exits might be and all sorts of clues (like "pheromone trails" or hand prints). It's clear that Rocksteady wasn't out to make a brawler - they remember rightly so that Batman is supposed to be the world's greatest detective, not the world's best boxer. Other components of gameplay in Arkham are collectible items and exploration. The game isn't exactly a sandbox game, but neither is it a straight linear path. Batman can go all over Arkham island (observe the mad gliding ability in the trailer), but certain areas won't be open to him at all times in the game. Some areas will require a certain item or a certain event to happen before they're open and it sounds like you can't really go back in the game unless the main plot makes do so.