Guild Wars 2

During the mission heart and mind, the rift opens up outside the island and its impossible to reach, i’ve included pics to show how it works

Hello,
I just recently got back into GW2, and have been wanting to try the new content from season 2 of the stories, but I just can’t keep my mesmer alive….. Is there a currently preferred PVE build that I should be using?
my guild that I’m currently in clasped sometimes before I made the return, sadly I don’t have the chance to run many dungeons so I use mainly gear i bought from the auction house, so is there a optimal gear set I can use?