Crystal Chronicled

Don't be like me and half research this achievement only to have to spend weeks waiting for it to be the only thing you need to finish for You Xal Not Pass. Three of the achievements for this part of the meta are timegated:

Children's Entertainer requires Work Hard, Play Hard to be up, which is a random world quest. You can only complete a couple of the criteria during each spawn of the world quest, so you'll either need to watch Hallowfall's world quests like a hawk or have multiple level 70s to complete this quickly. The associated world quest has been noted to be absent for weeks at a time— though since this is random, that may be anecdotal.

Beacon of Hope is related to the weekly quests from the Spreading the Light weekly activity, which are also on a random rotation. It'll take at least three weeks to get all of them, unless you get unlucky with which quests spawn, in which case it may take longer.

Lastly, Lost and Found is associated with a fairly quick series of three (well, technically five, but the first two don't count) quests that can only be done once per reset. This achievement will also take at least three weeks, though unlike Beacon of Hope it won't take more than three weeks, unless you miss a week.

So yeah, make sure you're doing Beacon of Hope and Lost and Found at the same time, otherwise this achievement will take at least six weeks, if not more for the world quest spawn.

Reference to Final Fantasy Crystal Chronicles at least! Any other options?

This meta-achievement is so much more involved than the ones for the other zones... it's kind of ridiculous.