Vier got a lot of different versions. One of them is a more tribal approach.

Those "Rottweil-Bears" in that version are an own Folk. Similar to Werewolves or Gorillas, they can both walk on two or Four legs. They actually "Shift" those forms like Werewolves to stay hidden from other cultures - perceived as mostly wild animals.

Ones in a while, those bears take a Vow of silence and travel through the "Vail" - basically using magic to travel to other worlds and such. They use the Animal form and the silence as a sort of meditation trip. This is the more wholesome version of Vier.

In this case, he stumbled upon a young mage about to unravel the secrets of different Worlds and their artifacts due to archeology and stuff... Renard being a smart bean quickly figured out that Vier isn't a wild animal, but makes a good companion!

Since Rottweilbears are considered pretty huge and strong, Renard can travel safely! In this picture, both travel through the "Old Sands" a very old desert.
Ones a blooming empire of Mages, a great war turned the rich land into a desert. The lingering Magic still drains the Land of most live - Except for the feisty worms and mutated insects who lurk beneath the sand to avoid those supernatural storms and wait for less prepared adventurers.
Vier being pretty much immune against both - carries Ren to those Artifacts.
The Sun and a "Sandship" in the background.

- Those ships travel the Old Sands and Old lands to traverse the gap between the new kingdoms. Normads and caravans, whole cities on those ever flowing ships - harnessing the Magic of those turbulent storms of Mana to trade and travel between the Oasis.