So let me get this straight.<br/><br/>For my character to do a Bull's Strength spell, he has to roll DC 30, -1 for casting it during three hours (DC 29), +6 to increase its duration to a couple days (DC 35), -3 for 6d6 points of backlash (DC 30),  then -2 for doubling backlash (DC 28).<br/><br/>Then, I could have Garrett take tens, since he has 18 SKILL?