Here is the full list of all 50 The Darkness II achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Find all 29 Relics in the single player campaign
Complete Vendettas Campaign
Survive the battle against the Hell Beast
Complete 6 Hit List exclusive missions
In Vendettas, acquire all the talents for one character
Complete a mission as Jimmy
Complete a mission as JP
Complete a mission as Inugami
Kill the NewsWatch 6 team of Tom Dawson, Bud Langley and Sara Stephens
Kill Frank Marshall
Impress Dolfo in two different ways
Max out all of Jackie's Talent Trees
Kill 50 enemies with Black Hole while playing as Jackie
Real guys know how to dance
Max out 3 of Jackie's Talent Trees
Kill 100 enemies with Gun Channeling while playing as Jackie
Kill 25 enemies while being dragged from the restaurant, without dying or restarting checkpoint
Finish the game on Don difficulty
Finish all chapters in New Game+ on any difficulty
Kill 50 enemies who are swarmed while playing as Jackie
Kill 15 enemies while playing as the Darkling
Throw an enemy into the air and kill him with gunfire before he lands
Earn a score of over 1000 in each of the carnival games
Kill 50 enemies with Executions while playing as Jackie
Kill 100 enemies while dual wielding 2 different guns while playing as Jackie
Max out 1 of Jackie's Talent Trees
Kill 50 enemies with thrown objects
Kill 2 enemies with one javelin
Finish the game on any difficulty
Kill 50 enemies with the Demon Arm Slash attack
Defeat Victor
Kill a shielded enemy with his own shield
Rescue Jackie from the Iron Maiden
Escape the asylum with help from the inside
Protect Jenny
Avenge your Aunt Sarah
Return to reality...?
Take back your mansion
Avoid being run over in the parking garage
Pick up 5 Relics in the single player campaign
Survive the interrogation
Refuse to cooperate with Victor in the Interrogation
Kill Jean-Luc Lambert and Amelie Dubois
Kill Cedro Valdez
Kill Luigi Palladino
Find and interrogate Swifty
Complete a mission as Shoshanna
Survive the hit
Purchase a Talent in the single player campaign
Kill enemies in 5 different ways within 30 seconds