Earlier this week, the Hall of Fame: Crown of the Cosmos has been completed with the 200 guilds having overcome the Mythic Alleria encounter. The Hall of Fame should be closing with the weekly reset this week, so if you want the achievement, you have around 2 days (depending on region) to get in those last few attempts and down the encounter.
Mythic Alleria has been criticized as an easier end boss due to the Race to World First, but the encounter can be quite difficult for underprepared guilds. Some of the most common struggles on this encounter are missing the Silverstrike Arrow in Phase 2 which shortens the enrage timer, and hitting all the immunities and positioning requirements in Phase 3.
Best of luck to all players who are going for the achievement in these last few days!
