Does the Lawbreaker ability increase your spells' power or just control? It says that it is a bonus to "all spellcasting rolls" but Power is not a roll.
As written it's only control rolls but that said i could see it adding to power and complexity to represent the increased power of darkness (like the others have said). My only problem with adding to the power and complexity is it may become too powerful for its cost if you do that. Not sure (since it causes hell to a character thematically) but it may happen.
And if it only affects control, why? Why would corruption by Dark Magic make your magic easier to control and direct?
Because your control with magic is how you visualize it (your magic) doing what you want by forcing it to with your will. Thus having lawbreaker means you've twisted yourself into breaking that law thus it's easier to visualize it happening again, meaning your control towards that outcome goes up.
Though again those said, since your conviction is your belief that magic should happen i cant see why it wouldnt give a bonus to that too.
