Re: death. Reathos built his Primordial Pool, which controls where spirits go when they die. It was not part of the Codex, but it was still part of the pre-universe creation process.
But yeah, being apart from the Codex puts it in the same category as dreams, with Illunbar's Dreamweaver. Does that make it inferior? Only time will tell...
Re: maths powers. You could navigate n-dimensional space. You could numerically simulate the outcome of the entire Universe, or some subset there-of. You'd have the ability to read and predict physics probably as good as Logos (he's still got the whole controlling physics bit, though). You could create incredibly intricate devices which function as computers (or actually are computers). You could invent whole new branches of mathematical reasoning. For Jvan, she'd get a whole lot better at fractals.
