These mobs come in pairs, and spawn during the protracted first boss encounter.

Attacks and abilities
Basic Melee: Deals roughly 6k to cloth.
Dismount: After a certain amount of damage, the rider separates from his bear mount.
Furious Roar: Physical debuff, targets take 25% more damage.

Strategies
These mobs are immune to crowd control, and need to be double tanked.