Chests

Every chest other than the wooden chest requires their respective key.
Ace Chests only spawn on the Archives and Chambers, with one guaranteed in the Forsaken Tower. Ace Keys can be dropped by Act 3 and 5 minibosses.
Each chest's loot percentages are listed below:

WOODEN

70% Common Item

15% Blue Diamond

5% Red Diamond

5% Ore

5% Uncommon Item

BRONZE

65% Common Item

35% Uncommon Item

SILVER

80% Uncommon Item

20% Rare Item

GOLD

65% Rare Item

25% Uncommon Item

10% Epic Item

ACE "Red"

50% Epic Item

50% Legendary Item