The Theomach is one of the Insequent. His true name was Kenaustin Ardenol.
In The Land's distant past, he traveled through time to gain knowledge of the Earth and the Earthpower. Once he collected it at all, he travelled to the Land and taught the meaning of the Seven Words, as well as much Lore to Berek Halfhand. When Berek travelled to the One Tree to make the Staff of Law, The Theomach came with him to challenge the Guardian. He defeated the Elohim, the Guardian of the One Tree, and became the One Tree's new Guardian. In doing so he was regarded as the greatest of his race, the wisest, the most powerful, and the only one to ever displace their rivals, the Elohim.
When the Haruchai travelled west into the lands of the Insequent, they encountered the Vizard and learned of the Theomach. The Vizard humilitated them, and informed them he was among the least of his people, that the greatest of them had travelled east, and entered the service of a powerful Lord. It was this drive to find and challenge the Theomach, whom they named ak-Haru, that led the Haruchai to the Land. Thousands of years later, in the service of the Unbeliever, they travelled further east again. Seeking the One Tree on behalf of the ur-lord, seeking nothing for themselves, they found the Isle, and were able to challenge the Guardian. Brinn of the Haruchai challenged him, and was quite nearly defeated, before accepting his death, and dragging the Guardian down with him as he fell.
Thus the Theomach, ak-Haru Kenaustin Ardenol, perished. Brinn of the Haruchai took his place as the Guardian. The Elohim scorn the Theomach for his arrogance, claiming much harm could have been avoided had he not interfered, that the original Guardian would have never fallen to a mere mortal, and the worm would never have been made restive.