What quests/missions are required for the achievement "Treasure Hunter"?

Question

Is there a guide anywhere thats tell you what quest you must have to be able to access all 20 chests?

Answer 1

It's the First Dragon Quest, which happens between January 14th and February 12th.

You can check it's details here:
https://tibia.fandom.com/wiki/The_First_Dragon_Quest

Answer 2

The following is a list of quests needed for access to the chests; 

Jakundaf Desert	No access Needed
Kazordoon	No access Needed
Treasure Island	No access Needed
Kha'zeel Dragon Lairs/Tiquanda	No access Needed
Banuta	No access Needed
Old Fortress	No access Needed
Draconia	No access Needed
Vengoth Castle	Blood Brothers Mission 8
Zao Steppe	New Frontier Mission 3
Crystal Gardens	Shattered Isles/Nargor access
Okolnir	Barbarian Test Quest
Drefia	No access Needed
Oramond Fury Dungeon	Dark Trails Quest- Defeat Death Priest Shargon mission
Krailos	No access Needed
Isle of Evil	Isle of Evil quest Mission 6
Spider Caves	No access Needed
Cemetery Quarter	Explorer Society (novice rank) In Service of Yalahar Mission 1
Ghostlands	No access Needed
Darashia Dragon Lair	No access Needed
Goroma	Shattered Isles Counterspell Mission completed