This is the most traditional end game of GW2, and how to actually start it can be unintuitive for players new to the game. It’s very epic and takes some time commitment (it took me three hours, though it could go much longer, and I assume much shorter if you’re lucky).
As a warning, this post may contain spoilers. I’m avoiding any major story points and sticking to strategy, but if you want to be completely surprised then avoid the body of this post. All you really need to know is that you have to unlock the dungeon Arah by completing the Cursed Shore meta event.
The step of your personal quest you should be on is “Victory or Death”. (I really hate that they chose a cliche name for that quest because it makes it that much harder to Google.) You can still do everything without being on this quest, but killing Zhaitan will also complete this quest for you and you might as well do both at the same time.
Zhaitan is in the dungeon Arah. This is a 5 player dungeon for level 80 players and you will need a group to complete it. It is located in the southwest area of the Cursed Shore. However, unlike the other dungeons, it is blocked by giant gates that can only be opened through world events.
You will need dozens people to complete these world events, though they’re not particularly difficult and require only a small amount of coordination that any pug should be capable of following. Since this is Guild Wars 2, you don’t need a party or raid to work together on events.
Clearing a Path
To start out, you need to travel to the Cursed Shore. This zone is, of course, located on the island of Orr. It’s a level 80 zone, and while you can be less than 80 to enter the zone, you need to be 80 to finish the entire quest line. Once there, you have to find the current meta event. I believe it starts at the northern-most way point, eventually pushing your way south unlocking more way points. Read the text under the meta event to approximate where the attack is currently.
(Note: The early stages of the event will tell you to go to Caer Brier, which I couldn’t find anywhere in this map. I’m 90% sure that’s a bug and they mean to say Caer Shadowfain, the northernmost waypoint.)
Preparing for the Assault
Once you find the current main event, you will travel south with a team of NPCs and a handful of players, gradually grabbing the attention of more players in the area until your group is quite large (we probably had 20 to 30 people with us by the end). Your final waypoint will be Anchorage Waypoint, which is where you stage the upcoming assault.
Once Anchorage waypoint is freed, three events will spawn, each one granting you an extra advantage once you head east to Arah, be it either cannons (not 100% sure on that one), a super powered golem, and npc backup. The group should try to split up and have three to five people at each event to ensure completion. Once Anchorage is secure, you will have around 10 minutes to complete all these events before the final assault begins. Any events not completed before the timer will fail.
One will require you to gather scrap metal to build machines. I think this event is slightly bugged because sometimes the scrap metal on the ground is an item that goes straight into your inventory (good), and sometimes it’s an item you can carry around (bad, the NPC doesn’t accept those). Rest assured that you will eventually find enough scrap metal. This is the easiest of the events.
Next is an asura who needs to summon her golem. I’d consider this the most important event, because that golem is a beast and can tank the upcoming bosses. You have to protect and escort her. If the crashed airship event is going on at the same time, sometimes mobs will get stuck inside the airship and you have to go around.
Third is another escort to summon additional reinforcements. It starts a little bit after the others, and while we were never able to successfully complete this event I think it should be pretty easy as long as you have more than one or two people working on it.