Unlockables

[TheDarkness]

What kind of unlockables are there and how will i be able to get them, besides calling a specific phone number. Are there unlockable packages on the roofs of buildings? Or maybe phone numbers on buildings?

id imagine youd be able to go on buildings by stacking cars to reach new heights with your demon arm, this is true?

[Jigsaw]

I know that Darkling outfits are unlockables

[cdstacker]

eating a particularly evil guys heart will unlock more darkness powers or provide a bonus boost to the heart meter as opposed to normal guys.