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IIRC, a lot of the Master weapon styles were originally supposed to be the tier-5 racial styles. Master's resto was tier-5 Breton, Master's sword (this was back before there was a shield to go along with it) was tier-5 Nord, Master's lightning was tier-5 High Elf, etc.
The tier-5 styles were never released, and eventually, many got reworked into the Ancestral styles. So Master's lightning which was tier-5 High Elf became the Ancestral High Elf style. The Master's sword and the Ancestral Nord sword are also basically the same. But the Ancestral Breton staff got reworked a bit so that it resembles the tier-4 staff rather than the tier-5 Master's resto, so unfortunately there's no guarantee that the Master's style will reappear as an Ancestral.
Anyway, Master's inferno was tier-5 Dunmer. Ancestral Dunmer hasn't been released (it surprisingly didn't come with Necrom).