Which ruler broke with the egyption practice of worshipping many gods and declared that egyptians should worship only aten the sun god

Akhenaten is the ruler who broke that practice. I think.

I think it is Akhenaten the ruler that  broke with the egyption practice of worshipping many gods and declared that egyptians should worship only aten the sun god. He is especially noted for abandoning traditional Egyptian polytheism and introducing worship centered on the Aten, which is sometimes described as monolatristic, henotheistic, or even quasi-monotheistic.

The holo caust ya feel me