Beat the final level in the Campaign. Not the secret levels, this is unlocked by completing the level where you beat Jin and Alisa.
Its a long level where you have to beat Kazuya, Azazel, Alisa and Jin. You should have no problem with Kazuya and Azazel, but when you fight Alisa, Raven should die quickly. One of the boxes at the front (near to where she spawns) has a lead pipe in it, it helped me a lot. For Jin the front TWO boxes have two different weapons in so use them wisely.
After you beat Jin the achievement should unlock.