Guild Wars 2

The last few days I have been trying to get the last few achievements for Queens Jubilee. One in particular is the balloon towers. Well most of the emissary events I was the only one running them. Now at the beginning of each one there would be one other just standing there helping at first then disappear (which most likely teleported). Which is fine with me lol more loot. Yet there are other runs I will do and someone will join in on the fun lol. When near the event they just disappear (now I do not see him/her running to the tower just poof and gone not any class that should be able to disappear out of site and still be right by you) and they show up at the top of the tower before I even make it there (with having full site of the tower not seeing anyone there). And this happens almost immediately after the gate opens that he/she is standing at the top. Anyone else experience this?

Could be latency on your end?

Not likely with my system and internet speed. That is one thing I thought of. Ping was good fps was good and no lag at all. But there is always that small chance. Though every time. And seems to be with the same characters everytime I see this happening.