Delver's Bounty is a random treasure map that can be awarded from the end of a Delve! It can drop up to Hero Track gear.
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Delver's Bounty is a treasure map that can be looted from the or at the end of Delves. This seems to be a completely random drop and according to Wowhead Looter (install to help our data collection), it has a 4% chance from each side chest in a Bountiful Delve (not the one that requires a key) and 0.12% from each chest in a regular Delve.
This Delver's Bounty drops at the Tier of the Delve you looted it on. If you complete a Tier 6 Delve and loot it, it will be Tier 6 Treasure map. Your next completed Delve of that level or higher will drop that level loot.
If you don't have Restored Coffer Keys, running Bountiful Delves daily could still nab you sweet sweet 610 loot if you get lucky enough to find Delver's Bounty.
We've received reports that Zekvir can show up in your Delve and chase you around. If you survive this onslaught, he may drop a map as well!
What do you get from the Delver's Bounty. We don't know all the lower tiers, but a Tier 8 will get you a lot of awesome things:
Here's what we know about the item levels of gear so far from Delver's Bounties.