Once Hodkamset was Sesostris, a wizard in service of Osiris but he had many enemies, especially among the clerics of Horus-Re, who managed to ruin Sesostris's reputation. So Sesostris faked his death, changed his face and name, and devoted himself to Set. He became the right hand of Seti, the current incarnation of Set.
Hodkamset was a member of the Fangs of Set. He had many spies across Mulhorand, many contacts inside Sampranasz, and an alliance with Zhentil Keep. His plans were to replace the young Pharaoh Horustep III with a rakshasa follower of Set in order to create chaos inside the clergy of Horus-Re, hoping to use this to gave the throne to Seti.
Hodkamset was very ambitious and a bit of a megalomaniac: he believed he truly was the one who could bring the rule of Set to Mulhorand. He was also very devious.