Comment: Well, one of the subclasses already covered that. Namely, the 'Prophet of Pestilence' shaman subclass.
But one of the most dangerous character, who i could came up also belongs to the Swarm-That-Walks. Basically any class, but with at least one level Crossblooded Sorcerer, and with one Mythic level for the extra Bloodline, all 3 increased to the max bonus by Ascendant Bloodline, add the Master Shapeshifter (it's good with the swarm form)