Guild Wars 2

I have encountered this issue on almost times I have been in the Grawl Fractal area, where you have to throw rocks on the Champion Grawl and there is a number of Veteran Grawl spawning that sometimes walk towards the captives and some that just teleport right over to them and as a result keeping my team from gaining the extra chest from that encounter.

This is clearly a bug or are we experiencing something super rare?

Second Grawl seems to always teleport.

First or second Grawl seem to Teleport for me. It’s random >.> but getting more and more less random