Arjuna explains how good his alteration is (Week 4)

With Alteration a total bust, you turn back to Reinforcement. Your first spell, your most reliable spell, your most powerful spell, and the one that pushed your existence to one that exists-as a fact of your biology-at twice the maximum level of human capability at all times. With it you could slow down your perception of time, empower yourself by who-knows-how much at this point, enhance the very concepts that made up your existence pretty much at will, take random sticks or pieces of paper and make them as strong as high-grade steel and unbelievably sharp, and so much more. Sure Projection could let you make stuff from thin air, but Reinforcement was your first spell. You had a bit of pride in it. And today, you cut down your Total Reinforcement speed by a whole ten minutes and even managed to figure out how to Reinforce individual body parts within a few minutes!