Flat Lust Achievement in Shadows of the Damned
Defeat Justine Boss
How to unlock Flat Lust
Story Related, Can't be missed
You will fight this boss in chapter 4-6. You will start the fight as you move to the right of the 2d world off the cliff, Justine will appear on the right side with 3 red spots on her face mask, shoot this with a regular shot until all three are destroyed, Avoid green slime/acid as much as possible by dodging or shooting them. After this immediately start using your light shot on her face again to drain her of green liquid. Once this is complete her face will be exposed you can then shoot her regularly but she will move to the left side of the screen flail her arms up slightly and then finally grab you, staying in the top left portion of the screen will keep you slightly safe from slime until she grabs you. While in her hand she will move you up and down towards and away from slime attacks while you continue to shoot her face. Just keep attacking her until she dies for good.