"I never fully explained it, did I, that day we found the first decoy that had trapped the soul of poor Minerva McGonagall?" Harry started. "So I’ll do it now. Riddle’s Horcruxes were complex, deliberate and brilliant pieces of magic, despite how dark and evil they were. They acted as soul anchors to this world, but each one cost him a little bit of what it meant to be whole and human ... namely his senses. He had to sacrifice all five of the physical ones, plus aspects of his heart and mind ... but it was a price he paid willingly, all for his stab at immortality.