For those who are relatively new, in the AC path 3 dungeon, during the part where you have to defend Tzark and destory a sequence of burrows, there is a pattern of where the burrows spawn.
Below is a screenshot of the spawn locations of the burrows and the sequence.
With arrows pointing to the next burrow:
The burrows can be easily killed using Frost Bow skill 4 and a Fiery Greatsword from an elementalist.
Tip on the fiery greatsword: Use skill 4 on the Fiery Greatsword and make sure you don’t have any target. Then run across the burrows. It should deal a significant amount of damage to the burrows. This works well on AC path 1 also, where you have to defend hodgkins and destroy burrows.
If you are kinda new to path 3, what you want to do is just ignore the gravelings and destroy the burrows first. Then you can kite/kill the gravelings while waiting for the next burrows to spawn; but you want to be in the spot of where the next burrow will spawn so you destroy it quickly.