One of the favorite tools of Tundra Orcs is also arguably their hardest to use. Its ceiling is as high as one would expect from an Epic Event, but it is very hard to find a good use that doesn't end with your summoner being highly punished.
It’s just a very powerful tool that makes your summoner a killing machine, but also requires a complicated setup to avoid leaving him too exposed.
Keeping it in-hand can be hard as you don’t know when the opportunity for good, tactical use will arise.
It can also be used as an escape tool with your summoner but that should never be the main plan.
Often too it can be combined with Freeze to make sure the opponent response is weakened, but holding both Freeze and Primal Fury in-hand can be hard.
Combining with Brutal Force makes this card a lot easier to use, but then you are using another event and the value becomes correspondingly lower.
Overall, how to use Primal Fury is probably the hardest decision a Tundra Orcs player needs to learn, and justice cannot be done to the tactics involved in even a paragraph.