From Dark and Darker Wiki
< What effects the multipliers in shapeshift?
the (1.0) means the https://darkanddarker.wiki.spellsandguns.com/Damage#Scaling Scaling is 100%. Anything that affects damage/healing will be applied at 100% efficiency. See the referred link for more info, but essentially ShapeShifts can be buffed all the same ways that everything else can, in addition to their base damage directly coming from one of the primitive attributes.