There have been a lot of changes made to The darkness 2 first and foremost the graphics have been changed drastically, rather than the dark, moody and detailed graphics of the first the second game has opted for more cartoony, comic style graphics and the big problem with this is the mood of the second game doesn't match the dark mood of the first game and the comics. The darklings have also had major changes where as in the first game you choose from four darklings that would attack the enemy directly, the darkling in the second (you only get one now) provides more of an assisting role when engaging enemies by restraining them while you're attacking and offering throwable objects during boss fights however the darkling does get a much larger part in the story and provides some comedy, the darkling also replaces the creeping dark darkness power from the first game but it only does this in two scenes so I think the developers missed out on an opportunity because I used to use the creeping dark move constantly in the first game and it gave a unique way to accomplish objectives.
The other three darkness powers from the first game (dark guns, demon arm and black hole) are all still present, albeit in slightly different forms, I'll talk about the demon arm later on and start with my favorite weapon from the first game: the Darkness guns. Sadly they have been replaced with an ability that empowers the guns your welding. The black hole has also been changed but only slightly as instead of just summoning the black holes they instead occasionally spawn on enemy bodies instead of hearts and is then picked up and thrown to activate. A new power has also been added called darkness swarm that sends a swarm of flies that blinds and damages enemies. The darkness armour is now actually visible which is an improvement from the first game however you can only ever see the hands. One of the best improvements to the game comes from the demon arms, where as in the first game you only got one arm that could only grab and had clumsy controls, in the second you get two demon arms, one that grabs objects that can then be thrown and one that uses directional slashing, this also means that this is the only game (at least to my knowledge) where you can quad wield (two demon arms and two guns).
The story I love as it really feels very much like a darkness story that would be in the comics and it is only improved by the voice of Brian Bloom (who plays Pike in the new A-team film. The vendettas (the online play) are also very cool as they provide background stories that follow on from events from the main storyline.
All in all although I was disappointed with the graphics and mood of the game the rest is jawdropping and this is definitely a game you should buy.