There are several Keys that can be obtained from Traders.
Once a player has obtained a key, they can right click the crate near their respective trader to open them. Players can also sneak while right clicking to bulk-open multiple crates at once.
Obtaining
Vote Key
Vote Keys can be obtained by trading 5x Vote Shards at the Vote Trader.
Pearl Key
Pearl Keys can be obtained from the Vote Crate, and Vote Parties.
Enchanter Key
Enchanter Keys can be obtained from Vote Crates, Pearl Crates, Pyrite Crates and Vote Parties.
Pyrite Key
Pyrite Keys can be obtained rarely from the Pearl Crate, Mining Crate, Farming Crate, Combat Crate, Fishing Crate, and Forest Crate.
Mining Key
Mining Keys can be obtained by trading 64x Diamond Blocks with Matt Allurgy.
Farming Key
Farming Keys can be obtained by trading 128x Hay Bales with Wheat A. Brix.
Combat Key
Combat Keys can be obtained by trading 5x Nether Stars from Captain Saltspring.
Fishing Key
Fishing Keys can be obtained by spending 2,500 Scales at Old Man Eyebrows.
Forest Key
Forest Keys can be obtained by trading 64x Resin Blocks from Clara Chairman.