Does any Mahayana school teach that I am atman?

Does any Mahayana school teach that I am atman, the Self of buddha nature? Assuming a resounding "no", may I please ask, if atman is "like" anything, or is it more like the eventual non existence, annihilation, of the empirical self, like death is for philosophically enlightened atheists? It is not true that qualia are substances, not only in Western philosophy, but in Buddhism too, because otherwise the skandhas, being insubstantial, would not be like anything! Perhaps that question is unanswerable, because I can't see any alternative to those possibilities !