We find the myths of the combat between Set and Horus evolving from a simple opposition of day and night into a combat between the two gods. Ra and Osiris, instead of Horus, are sometimes ranged against Set. The combat symbolized the moral idea of the victory of good over evil, and those of the dead who were justified were regarded as having overcome Set as Osiris had done. In his combat with the sun-god Set took the form of the monster serpent Apep and was accompanied by an army of lesser serpents and reptiles of every description. In later times we find him identified with Typhon. All desert animals and those which inhabited the waters were regarded as the children of Set, as were animals with red hair or skins, or even red-haired men. Such animals were often sacrificed ritually in propitiation of Set. In the month Pachons an antelope and a black pig were sacrificed to him in order to deter him from attacking the full moon, and on the great festival of Heru-Behudeti such birds and fish as were thought to be of his following were trodden underfoot to the cry that Ra had triumphed over his enemies. Set had also a kingdom in the northern sky, and his peculiar abode was the Great Bear. As in some other countries, the north was considered by the Egyptians as the place of darkness, cold, and death. Thus we find that by the Mexicans and Maya the abode of the god of death was considered to be the north, and that among the latter people the hieroglyph for the north is a human bone placed before the head of the death-god. The goddess Reret, who has the head and body of a hippopotamus, was supposed to have the evil influence of Set in restraint. She is pictured as holding darkness fettered by a chain, and is considered to be a form of Isis. It was probably about the Twenty-second Dynasty that the worship of Set began to decline, and that he took on the shape of an evil deity. The theory has been put forward that the Hyksos invaders identified him with certain of their gods, and that this sufficed to bring him into disrepute with the Egyptians. Set and the Ass Plutarch, in his _De Iside et Osiride_, has an interesting passage concerning the alleged resemblance between the ass and Set. He says (the translation is the old one of Squire):