Think of were shapeshifting as an advantage with a variable cost. That cost is 15 plus the template (the template is "inside" the advantage, not separate from it). When you apply any modifiers to the advantage, you modify the entire cost, not just the 15 points.
Does that help?
-- Bob
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Then the horns kicked in...
...and my shoes began to squeak.
Does that help?
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.