I know they can be found in ether key chests, but I'm curious if they can be found in the 2 chests that appear after finishing the prison of elders also
There are a number of ways to get a treasure key for sure:
- Complete the House of Wolves story missions
- The first Wanted Fallen bounty you complete each week
You can also possibly get a treasure key from the following:
- Opening an Ether chest
- Opening the small chests at the end of Prison of Elders
- Queen's Packages
+1 - the first Wanted Fallen bounty you complete each week is probably the easiest way to obtain a key. I try to do these on each of my characters per week first. The bounties are available from the Queen vendor on the Reef.– Travis JJun 9, 2015 at 20:14
Treasure Keys are used to obtain the ultimate loot after finishing any given Prison of Elders run. Guaranteed ways to obtain 1 key:
Complete the HoW story missions Complete a Prison of Elders mode Only 1 key will drop perk week
Try your luck:
Ether Chests from Wanted bounties Small chests in the PoE Treasure room
“What does it unlock?”
There are multiple chests in the Treasure room, and only one requires a Treasure Key to unlock. This ultimate chest will have the chance at rewarding Exotics, Legendary Queen gear, Fallen-themed cosmetics, Strange Coins, & Motes of Light.
The smaller chests, which do not require anything to unlock, have the chance at rewarding Strange Coins, Motes of Light, Planetary materials, & even Treasure Keys on occasion.
You can use 1 Key per chest, and there’s only 1 “Treasure Key Chest” per run.
All from: http://planetdestiny.com/prison-treasure-key-guide/
Treasure keys are not a guaranteed reward from Prison of Elders. They have a chance to be in the side chests, but aren't guaranteed. I have ran Prison of Elders 3 times, and haven't received a Treasure Key from any of the runs.– AdeeseMay 22, 2015 at 11:39