Dumbledore had given him a few lessons on Horcruxes, while Harry pretended, wide-eyed, that he’d never heard of them before, but he’d stopped early on last term when he had apparently gone to find the ring and come back empty-handed. It had disconcerted him, Harry knew, and from hints Dumbledore had dropped around Hermione when she was studying the books he recommended, he was now looking into alternate methods of immortality Voldemort could have used.