Second second dungeon key?
 

Yes, I meant to type that twice. What do you do if you get a dungeon key twice?

just sell it or keep it as a souvenir it doesn't really matter. Sometimes you might get extra key for the same dungeon that you have yet to unlock.

You should not get a key for a dungeon you have unlocked. However, if you haven't unlocked the dungeon, then the key is still prone to show up in your quest rewards instead of the regular item. You can sell them to the shop, but I don't think you get much gold at all.

yes indeed Bullbound is right. I bring my apologies for misinformation I meant if your dungeon is not unlocked yet because I think that's how I saw my extra key in a quest. I forgot to unlock the dungeon with the current one if I remember that correctly. I editted the previous post to reflect that.

I might add that I "sold" a dungeon key and got 0:gold: for it!

Nobody wants to buy a dungeon full of evil monsters so you get no :gold: . :)