If the horde comes with high density or (in my last case) iron breaker taunts a significant amount of enemy they simply go through the player. Now the player is instantly bodyblocked by them and the other enemies who are not taunted by bardin begin to hit to death, because your block is broken in 1 second and you cannot dodge not even move a bit.
How to reproduce: play the game. This is a common issue since ages.