I've played violent games for far too long to have all the borders blurred between violent and not-enough-violent game. Just then comes a differentiation of a well-done violence and poorly done.
It depends on what you cosider as a legitimate violence.
If realistic killing, then it's whether Max Payne 3 or Hitman: Absolution. Fair to include Cortex Command here, it's rare you can shoot the guys head off to a gazillion of pieces. You gotta see it to understand what I'm saying.
If moar blood and gore, it's whether Garry's Mod's Dismemberment Mod or, as stated before, Postal 2. Also, MGS 5. It's enjoyable to kill out there. They die just right. (don't look at me like that ). Also, Killing Floor, both. Also, as stated, God of War.
If torture, see The Torture Game 2. It's flash.
I expected more from Hatred. It had that controversy, but ended up just the same as Postal. Meh, totally meh.