Two Renegade Realms

In book two of Donita K. Paul's Realm Walkers Series, Cantor, Bixby, and Dukmee band together to find the storied realm walker Chomountain after the attack by the corrupt Realm Walkers Guild. But the great wizard is not as he once was, and they must now find a way to restore Chomountain before they can repair the guild once more.