Illa is one of only two named members of the younger generation of Big-Raven's kin in Koryak oral literature (the other being Kilu). Usually described as a nephew of the Raven, he assists the creator's household through its many adventures. In the widespread pattern of cousin-marriage that structures the tales, Illa is paired with Yiniaaneut, Big-Raven's eldest daughter, just as Kilu is paired with Big-Raven's son Ememqut. A variant narrative instead makes Illa the son of the creator Tenanto'mwan, an aspect of Big-Raven himself.