[Note: There will be spoilers for BioShock: Infinite and Killer7, possibly NSFW content as well. Also, first blog ever, woo!]
Meet preacher Witting, the most violent figure in BioShock: Infinite.
He's a blind priest. His sacred duty is to guard Columbia's entrance. He cleanses you of your ghastly sins from the Sodom below, and births you anew, fresh and clean in water blessed by the Founders themselves, brought up into the heavenly sky by the chosen people, for the chosen people, you.
Meet Curtis Blackburn, one of the most, if not the most, violent chaps in Killer7.
Blackburn is a sadistic, vile, horrifying monster that resembles a human being. A pedophile, organ trafficker, criminal, cruel hitman and a merciless, frightening construct of hedonism to the extreme.
What might connect the two, you ask? How does a priest compare to a serial killer? How do two very different characters from very different games even begin to fall into the same category? Well, it's all a matter of perspective.
Perspective is touched upon in both Infinite and Killer7, in various degrees through the gameplay itself and the content presented throughout cutscenes and in-game lore. Infinite uses the multiple universes theory to directly communicate about the medium through the medium (how well this is actually done is going to be debated seemingly forever), while Killer7 talks about the dissonance between the East and West on a cultural and social scale by abusing the medium entirely. For both games, violence serves as an important, active part of the medium, and both of them would lack impact and meaning without its inclusion. How violence is portrayed and used is, accordingly, quite different.
Infinite juxtaposes the peaceful, serene setting of a city in the sky with brutal killings of its very own citizens and their protectors, along with systematic torture and indoctrination of Elizabeth, to make a point. Killer7 is a constant stream of violence and gorey acts of bloodletting meant not to shock anyone, but to be par of the course in its alternate reality as a means of interaction.
What this means is that a violent act in Infinite cannot be measured by the same standards as a violent act in Killer7. Violence in these two examples is not taken from a general definition that's applicable in reality, or indeed, in other works of art. The key characteristic and reason why this subject pops up over and over as a recurring theme in videogame fandom is because the violence in videogames is interactive - and as such bears more weight than a description or presentation of violence.
If virtual violence in games is something powerful and unique to the medium, then why wouldn't you use it to send a message? Why wouldn't you make a violent game if you want to make an impression? That's not to say that Pac-Man should now become a ghost molester and replace power pellets with a Jack The Ripper Introductory Surgeon Kit to make it more violent and thus more meaningful, of course not! But it does mean that considering violence as a negative thing by default in the context of videogame design and game appraisal is severely limiting and hampers the medium to a significant degree.
Blackburn's death is a perfect example of how Killer7 handles brutality from more than one perspective. As you play Curtis' chapter, you're killing plenty of Heaven Smiles along the way, and bear witness to Curtis' wrongdoings, which include, but are not limited to; beheadings, executions, rape, sadism and even brainwashing. At one point you yourself kill his lolita protege without remorse. Dan Smith, former associate of Blackburn, engages in a duel with Curtis after some insults on both sides - it is implied Curtis killed Dan the last time they played the same game. The boss battle then becomes a 180 turn on the usual Killer7 gameplay - all you need to do is shoot Curtis 4 times when the bird flies, faster than Curtis can shoot you 6 times. That's it. There's no brilliant or innovative gameplay mechanic that makes the act of killing Curtis a memorable boss battle - it's the fact that you kill Blackburn as a clean-cut, efficient killer, a polar opposite of Curtis' "ways of shining light on his life". Pulling the trigger on Curtis is made to be exhilarating and rewarding by the very nature of why you're shooting him in the face - Curtis' love for violence is brought to a swift end by your violent hand without you yourself (a.k.a. Dan) falling into the same trap along the way. You dissasociate the violent act from a statement of your personality, yet you are aware such an act can be a statement. Dan hammers this home calling Curtis "a sick maniac" and robbing him of a death fit for an assassin, mutilating him the same way he did countless others - this does not make Dan (or the player) an equally sick maniac.
Back in Infinite, Booker is going around Columbia killing racist bigots left and right, some civilian, some not, and then later starts ripping through the more racially diverse Vox forces with equal measure. Elizabeth supports you on the side, naturally. Now, how can Booker, even with his Pinkerton background, even with the regretful experience at Wounded Knee; how can an American soldier murder Americans (regardless of colour) in cold blood? How can any soldier willingly engage in killing after PTSD? Is Booker "nothing but a sick maniac"? The game solves (or tries to solve) this surface dilemma by providing convenient memory restructure due to reality shifts - but if you look at it from a deeper, more contextual point of view, you can see a different picture altogether.
The baptism as the turning point between Booker and Comstock serves more than just as a knot in a time-loop - but rather becomes the single most violent act in the entire game. Witting cleanses Booker of his sins - it is a purge of Booker's violence. This purge causes Booker to go in denial and clothe his regret in religious zeal as Comstock. The Booker that refuses the baptism accepts his sins, but proceeds to linger on them, which robs him of his future with Anna. The baptism and its priest, then, never result in a happy ending. Whichever option Booker goes through, it ends in death and/or misery. If it were not for the Luteces (i.e. the equivalent of a higher force/being), Witting would doom all Bookers that came to answer his choice with a yes or no. It's not about what you chose then, it's about the fact you had a choice to begin with. Witting managed to (unwillingly) perverse the human ability to choose into torture, spawning infinite realities that did occur and always ended badly.
(I'll have you know I shower daily, you fiend.)
Witting basically comits ideological assault, and Infinite's opening serves the exact same purpose. You're drowned against your will by Witting (even earlier, in the lighthouse, you have already refused baptism, and yet your resistance is pointless.) Your first hint of Columbia is that it's a crazy place and yet - Columbia is a beautiful place, and for a moment you can see it functioning perfectly. Heavenly. It is not a coincidence Columbia shows its claws right after you get a "choice" for the first time. Those first few dozen enemies are dealt with the Skyhook - why? To separate the Booker you're playing as from the Comstock that's hunting him. ("But who is that man who lies submerged? Perhaps that swimmer is both sinner and saint, until he is revealed unto the eyes of man.") The violence Booker partakes in is gruesome and jarring, but Booker is not reveling in it, while acknowledging he has no choice in the matter. His violence is not a statement, but a means of traversal. Comstock's violence is a statement, a result of oppressive ideology that spreads like a virus throghout Columbia and is keen on blowing up "the Sodom below."
(Fighting the Vox, however, is a different matter - since Daisy considers Booker "not part of the narrative," it can be argued Daisy wants to continue using DeWitt's image as a martyr for the cause, or just as yet another commentary of the medium - either way it results in fighting people who were allies moments ago, and I don't think this was pulled off quite as good, so I'll refrain from saying anything further for now.)
(Dead, alive, what's the difference?)
What it comes down to is that the graphic violence in Infinite pales in comparison to the mental assault on Booker's (and your own) senses. Columbia is disgusting not because of the melee executions and vigor explosions, but because the people getting blown and beaten are willing to consciously stand up against what Booker (the player) thinks and acts upon. Columbians are not mutated Splicers or stereotypical Nazi soldiers or legions of Fett's clones. They're people who subscribe to a different idea - an idea they're willing to kill for - an idea they're willing to impose upon you with force and impunity. And all of it stems from a single person who chose a perspective that coloured the world around him.
So when it comes to the polarising reception of Infinite, and the subject of "unnecessary" or "excessive" violence present in the game, it seems to me that's missing the point entirely. The visceral contact, the lack of any other option, serves to fuel your understanding of what oppression truly is through gameplay, and this is backed up with accompanying lore through voxophones and level design. The Handymen with their cries of "Stop!" and "Why are you doing this?" are the prime example of how a corrupt idea can turn you into a tin man (as per Slate's Hall of Heroes episode). Removing violence from this equation would dull the impact and destroy the experience.
To conclude (I'm rambling far too much here); violence in videogames isn't necessary, of course, it depends on the game in question. But to argue that there is too much of it (or too little), and to not appreciate what violence can do in the medium (keeping in mind no other medium can do this) is somewhat shortsighted. These two examples of violence are just the tip of the iceberg - but it's a very sharp tip indeed. If games themselves can view violence from various perspectives, unique because of interactivity - why do we run from it?