the first MMO I ever played was City of Heroes (no longer exists). In it, we had a single mission that created a lot of friendships and probably was the key to the creation of a lot of guilds.
that mission was Frostfire (if anyone remembers it who is on here...)
It was a multi layered mission set to lvls 13-16 if I remember correctly. One time, I went in as a lvl 13 with a bunch of others that were lvl 13 and one lvl 16. All the spawns were lvl 16!
That group got wiped out like 20 some odd times, but we did complete it!
Frostfire was famous for the ice-slides that would have characters making spectacular jumps.
Anyway, the point of this question was: is there any mission in AoC that everyone does repeatedly with every character they make in which he or she MUST be in a group to complete it?