King Peribsen
The name of this pharaoh is not present in any of the lists of kings that have come to the present day but has been found on several monuments. At Umm el Kaab, Petrie discovered two tombs at the opposite ends of the dynastic necropolis, one very small belonging to Peribsen, and the other of an exceptionally elongated shape to a king Khasekhemuy.
Peribsen's serekh has an unusual feature of being surmounted by Seth's animal, rather than the usual Horus hawk. In the tomb of Peribsen seals of jars of a certain Horo Sekhemyeb were found and at first, it was assumed that this was the name of Horo of Peribsen himself, even if this conjecture was contradicted by the presence of God Seth on the serekh of most seals and two beautiful granite steles placed in front of the burial chamber.
2nd Dynasty Kings of Egypt
A subsequent excavation not far from the tomb brought back the name of a king Sekhemyeb Perenmae and it was believed then that it was a predecessor of Peribsen; later the same full name was found on fragments from the Step Pyramid. Grdseloff's hypothesis that Sekhemyeb Perenmae is none other than Peribsen before betraying Horus to become a fervent devotee of Seth is very likely.
He was interred at Abydos, the site of the discovery of a seal inscription that included the first fully composed hieroglyphic sentence.