So if I were to cast Magic Weapon, which increases the damage dealt by one weapon by 1d4 and imposes a −1 ongoing to cast spells, and Empower it; would both the positive effect and the negative (−1 ongoing to cast) be doubled?
So is it:
+2d4 −2 ongoing to cast, or
+2d4 −1 ongoing to cast, or (though I think much less likely)
+2d4 −0 ongoing to cast?
The reason I ask is because I expect to be doing this in times of dire need and it would be good to know beforehand just what the spell will do.