What the achievement asks
The six renown questlines of the Dragon Isles. Account-wide, both factions.
These are not side quests you can go and find: each one unlocks at a renown threshold with its faction, and until you are there it does not exist.
The six, and what each waits for
| Questline | Faction | Renown |
|---|---|---|
| A Mystery, Sealed | Dragonscale Expedition | 13 |
| In the Halls of Titans | Dragonscale Expedition | 24 |
| The Chieftain's Duty | Iskaara Tuskarr | 11 |
| The Silver Purpose | Valdrakken Accord | 12 |
| Garden of Secrets | Valdrakken Accord | 19 |
| The Dreamer | follows Garden of Secrets |
The Dreamer has no threshold of its own: it begins the moment Garden of Secrets ends, picking up from that chain's last quest.
This is a reputation achievement wearing a quest costume
Nothing here is difficult. The whole cost is the renown, and the highest bar is 24 with the Dragonscale Expedition.
The good news is that you need far more than that anyway: Oh My God, They Were Clutchmates wants Renown 25 with the same faction and 30 with two others. Push the renown for that achievement and these six questlines unlock themselves on the way past.
The Silver Purpose is worth doing the moment it opens, because Of the Tyr's Guard is locked behind it, and that is a piece of a different branch entirely.
Where the first quest actually comes from
Reaching the renown threshold does not put a quest in your log. Each chain has its own starting NPC, and finding that NPC is the part people get stuck on.
A Mystery, Sealed is the clearest example: at Renown 13, Doc Nanners offers A New Mystery, which sends you to Naleidea Rivergleam at 47.86 82.47 in The Waking Shores. Nothing about the renown notification tells you any of that.
If you have the renown and no quest, do not stand at the faction's renown herald waiting. Go to the questline's own starting NPC. Several players have reported exactly this with Garden of Secrets, The Silver Purpose and The Dreamer, all convinced they were bugged.
Do them on one character
None of these six questlines pays reputation, so running them on an alt gains you nothing beyond the story. The achievement is account-wide, so one character clearing all six settles it for everyone.
They are also short. Players who rushed to the last one, In the Halls of Titans at Renown 24, describe it as a brief chain with little at the end. Do them when they open because they are cheap, not because they are worth hurrying to.
Where it fits
A piece of A World Awoken, the Dragonflight meta.