An enormous humanoid with webbed feet and glowing red eyes, Ithaqua frequently stalks the Arctic wildernesses where he preys on the unwary. Regarded as having been the inspiration behind the legends of both the Wendigo and the Yeti, many of those who dwell in Ithaqua's hunting grounds leave regular sacrifices to this fearsome creature- not as acts of obeisance, but rather in an effort to appease the beast.
Any whom he does catch is dragged off to Ithaqua's true home, the ice planet of Borea, to swell his growing band of worshipers. Here, he will attempt to mate with any females by inserting a psychic "seed" into the womb, which will develop into his offspring, in an effort to create children whose abilities will outstrip his own. He hopes that one day, one of these children will aid him in his goal of freeing the other Great Old Ones and, ultimately, in destroying the Elder Gods once and for all. However, in all the many years of his existence, none of these children has ever lived up to his dreams, and every one has turned on their father.
In addition to his cult on Borea, Ithaqua makes use of the of the Shantaks, a race of oversized avians who reside in the Dreamlands, and is known to have a number of powerful air elementals at his disposal. He was also worshiped by the race of subhuman cannibals known as the Gnophkeh, before their demise during an ice age brought on by Ithaqua and Aphoom-Zhah.
Single-handedly responsible for the destruction of an entire Swedish army in 1718 during the incident known as the Carolean Death March, Ithaqua also attempted to assassinate long-time foe of the Great Old Ones Titus Crow at least twice. The first time he sent some of his most powerful elementals to destroy him in his own home, but Crow and his friend were able to effect an escape in the time machine known as ‘’De Marigny’s Clock’’. On the second occasion, he came for Crow himself when he was traversing the cosmos in the Clock, but Crow was able to use the machine’s inbuilt weapons systems to fend off the monster.