The rituals question he had been carrying since January. He had a list --- not the Horcrux list, a different one, in a different notebook --- of what he wanted and in what order and what each one required.
The principle was the same one he applied to everything: from the constraints outward. He was not trying to become something other than himself. He was trying to become more fully what he already was, which was a different thing and required different methods.
He had read everything available in the Hogwarts library on ritual magic by October. He had read the restricted section material by December, with the permission slip Lupin had signed without asking too many questions. He had read the Black library texts over Christmas, sitting in the study at Grimmauld Place while Sirius slept late and the house tried to be less hostile than its nature inclined it toward.
The available material gave him a framework and a significant number of gaps.
The framework: ritual magic worked on the principle of equivalence. You could not take without giving. The more significant the change you were asking for, the more significant the thing you had to offer --- not sacrifice in the dramatic sense, but investment. Time, attention, material, sometimes a piece of something that cost you. The magic assessed the offering and returned what it judged equivalent.
The gaps: most of the texts were either too theoretical to be actionable or described rituals so specific to particular traditions that they could not be adapted without risk. The Black library had better material than Hogwarts --- the Blacks had been serious practitioners for centuries and their library showed it --- but even there he had found himself at the edge of what was available in Britain.
Which was why Uganda mattered.
The rituals list, as it stood at the end of March, had four items.
The first was the animagus transformation, which was not technically a ritual but operated on the same principles. He would do this at Uagadou in July.
The second was a perceptual expansion ritual from the Black library --- a working designed to heighten magical awareness, the ability to sense and read ambient magic more precisely. The cost was significant time in an altered perceptual state and the offering was a genuine memory given to the ritual.
The third was a strengthening ritual referenced in three sources, none of which described it completely. The fragments suggested it increased the depth of the magical core --- the speed of recovery and the efficiency of expenditure. He needed the full description from Uganda practitioners before committing.
The fourth he had not decided on yet. He had a shortlist. He kept it in the notebook and waited for the answer to arrive.