[2020] Guild Wars 2 Fifth Anniversary is LIVE

Spike zerged basically means that, with regards to the TT encounter specifically, they'd organize into 4 groups. They'd have roughly 10-15 people for 3 of the groups, and then one massive group of 100+ players. They'd start off with the zerg group, and one of the smaller groups at Amber Wurm, trigger the vulnerability, and spike it down to 10% or less and then stop. Then the Zerg would waypoint away and go to Crimson and do the same, and then Cobalt. They were able to get the wurms all down very quickly, but they had trouble managing the coordinated kill check from that point.

TT was really just a big evolution of Teq. Overall the server performance improved with the Teq redesign since we were promoting players spreading out more (to the batteries) but it still suffered when he went vulnerable since all 100+ players were using their skills at the same time in one concentrated point, which is the main issue we're trying to solve. That's why TT (and more recent World bosses) have put a lot of effort into either spreading out the players across the map, or limiting the number of players accessing the boss at one time like Vinewrath.

There are a number of things going on behind the scenes in that map that are unique in its structure compared to other open world maps like Sparkfly Fen. The number of agents in the map overall are considerably reduced for starters. If you zone back to other waypoints in the map during the final encounter, there isn't a ton going on. In the encounter itself, a lot of the difficulty in that encounter relies on the named Legendary creatures you fight (Hareth etc), instead of huge waves of scaling creatures like Teq. There also aren't any active events going on at the same time as the final encounter. One issue with older open world maps is that there are probably a handful of players running around who aren't participating in the world boss at the time. So that means additional events and spawns that take up some amount of resources. Dragon's Stand is designed to funnel everyone to the same place.

Also, the programmers have been making tweaks to the game for years to optimize things! We have a lot of tools now to build content we didn't have when the game shipped that are much more cost efficient for the game.