Walkthrough for the "Tribes of the East" expansion.

Kujin's upgrade should be adequate (e.g., a super ability + Darkness spell), and only the necessary artifacts should be equipped. In battle, use Horde Fury and Frightful Howl. You can try to position a wyvern to take the first hit, which might cause the dogs to attack immediately instead of summoning reinforcements. Goblins disrupt magic. Protect the shamans (they were the last ones I had, and they killed almost all the dogs, and the opponent even helped by casting Berserk on them). Something like that. It's difficult to win, but possible.