It is not too big of a deal to clear dungeons if parties could attempt it multiple times. Though a fraction of players might not be able to clear it, most parties possessed the necessary strength, and it is a given fact.
Furthermore, whether a commander is adept is dependent on acute observations and his sharp senses. Amber Sword Heart was one such commander as he could speedily devise a tactic against Earth-shattering Bull King despite facing it for the first time.
Taunts were a no-go, as they would definitely get trampled over. Thus, he proposed that a main tank bait it and run in circles.
When Earth-shattering Bull King was not enraged, its movement speed was not that fast. Despite that, kiting it still was not easy. This was due to the Tremor effect that happened as Earth-shattering Bull King ran. Should anyone get too close, they would easily trip, and if the hooves landed on them, they were as good as dead.