The interesting thing about the Catwoman alternate ending in Arkham City is what doesn't happen if you don't choose to have Catwoman help Batman out.
This discussion of Batman: Arkham City contains spoilers.
Rocksteady's Batman franchise features a very competent Batman by allowing the player systems of play that make playing well very easy. That ease at which the player can slip into Batman's skin makes some sense, though, since playing a caped crusader that fumbles about at his job would violate the iconic, nearly inhuman qualities of a character whose stock and trade is supreme competence.
That being said, Batman is not quite the same icon as Superman, nor is either one like their Marvel counterparts. Emotional vulnerability and self doubt plague the very humanly drawn characters of the Marvel universe. DC characters most often seem more like gods than men, as they deal not with personal issues but problems of global concern: crime, terror, fear. A vulnerability in Batman that is not emotional or professional, however, is still present in Rocksteady's version of this DC character (who most often feels less like a human being than an archetypal force of vengeance). Batman is still human, and unlike Superman, he can bleed.
In the first game, Arkham Asylum, Batman's vulnerability is made plain through the changes that his body undergoes over the course of the game. Time passage is not often so graphically portrayed as it is in Arkham Asylum, in which damage that the Batman character takes over time is represented on his body. From torn clothes and shredded cape to open wounds and the appearance of stubble as the night in the asylum wears on, Batman looks like he has been through something over the course of the game. Ultimately, the physical vulnerability of Batman is intended to show some sort of emotional fortitude. Despite tattered cape and slashes across his face and torso, if the player hangs in with the Bat throughout the game, he will see that Batman can always hang in there as well.
If this all sounds a bit macho, well, sure. Batman falls squarely into those traditions of male power fantasies writ large for little boys to admire and emulate that are old school comic books. Batman's endurance, despite his lack of invulnerability, is a piece with such interests. A man is supposed to be able to “take the pain.”
Batman's physical vulnerability is once again on display in Arkham City, in which clothing and bodily damage both increase over the course of the game, marking the movement of time and also the endurance of the Dark Knight. Interestingly, here, though, despite the self reliance of the character as presented in the first game, Batman is “tempted” early on in Arkham City by an offer of help by his sidekick Robin. Robin appears on a rooftop and suggests that he can be of some assistance in this less than hospitable place populated by a prison population. Batman brushes Robin off, finding another task for him to complete in a less dangerous area outside the prison-city, choosing to go it alone amongst city blocks of super villains and other criminals.
Clearly, this sequence largely exists as a bit of promo material for some of Arkham City's expansion packs, which include expansions for a playable version of Robin, and I didn't think much about the sequence when I was playing through the game. However, that was before I was made aware of the alternate Catwoman ending of the game, and I began thinking a bit about how Batman is actually “helped along” throughout both games, though never much by male characters, only female characters.
Arkham City utilizes a conceit that exists in many other video games, the use of an NPC as a “guide” through the game's missions. Here, as in Arkham Asylum, Oracle serves as the voice on Batman's headset, offering occasional pieces of advice, voices concern, or tracks down leads for Batman outside of his current zone of influence. Admittedly, Oracle has served this role in the comics as well (for characters other than Batman, too), but this idea of a female voice acting in a support role as guide or adviser or just as cheerleader is one that is altogether common in action-oriented games with male protagonists. Cortana serves this role frequently in the Halo series, for instance.
If Batman seems to need only a little female support, then, in the form of cheerleading and concern for his well being, the alternate Catwoman ending suggests a much greater lack of pure self reliance on the part of our rugged hero -- a dependence that is made clear through the systems of the game itself.
Throughout Arkham City, the player is given the opportunity to play as Catwoman in a subplot concerning her “reacquiring” some goods that were seized by Hugo Strange. In the culminating mission in her story arc and after the player has managed to successfully get a hold of these goods, Catwoman is on her way out of the confines of the superprison that is Arkham City when she is made aware that Batman is at the mercy of the Joker.
The player is then offered a choice: to go to Batman's aid or to escape with her twice ill gotten gains. As I imagine many players have done, I opted to save Batman during this sequence and promptly forgot that a choice had been made at all during the scene, as the story continues apace. The interesting thing about the sequence, though, is that the game doesn't “continue” if you don't choose to have Catwoman help Batman out.
Instead, the credits for the game roll and the news of Batman's death reaches the player in this conclusion to the game. In other words, the message is clear: despite the depths of Batman's physical endurance featured bodily in both games, he just can't make it without the intervention of another character, his female counterpart. The game insists on this idea by mimicking a terminal state to gameplay itself. The “Game Over” screen that has largely become obsolete in modern gaming (as it once marked the failure of the player, the need to “do it over again,” rather than offer the chance to continue as it most often does now) is supplanted by what gamers recognize as the “way that a game ends,” with cinematic style credits, since the story and game have been resolved “correctly.”
As I mentioned earlier, Batman is less a character recognized for his humanity and relatability than he is understood as an archetype and force. Unlike, say, Peter Parker, Bruce Wayne is not really so much a man who disguises himself as a bat than he is whatever it is that Batman represents, with Bruce Wayne serving as disguise for that mythic figuration, not vice versa. In this sense, many of the traditional roles of masculinity that 1940s comic books and contemporary video games suggest to their male audiences exist in the iconic representations of masculinity that many super heroes have come to represent. Batman is, like your dad is supposed to be, just about the most competent man in the world, tough as nails, and while he can be beaten, he cannot be broken. However, that masculine self reliance is only tempered by the necessity of eventual partnership.