In Spleunky 2 there is a golden key that you can find while on your runs. Check out this guide to find out where to use the Golden Key in Spelunky 2. This way you can get the extra loot and the extra money for your runs.
Where To Use The Golden Key In Spelunky 2
Finding the Golden Key in Spleunky 2 can be a bit difficult. The Golden Key will generally start to drop in 1-2 and beyond. When you find the key, make sure you pick it up and hold it in your hand. You have to be holding it or you will lose it. From there you have to find the random doorway in the level. It will be somewhere, just keep looking.
Once you find the door, go inside and you will find a golden chest at the top of the area. Open the chest and inside you will find the Udjat Eye inside. The Udjat Eye will let you see the gems that are hidden in the walls so you can get them easier. This is similar to the glasses that you can buy in the shop if you have enough money. You can also use the key as a weapon if you want by tossing it at enemies. The key is pretty durable so you can get quite a few shots off with it before it breaks.
I think the Udjat Eye might be used somewhere down the line to trigger an event or open a chest, but I am not sure yet. If you find a spot where you can use the Udjat Eye, leave a comment and let us know where to use it. Check back soon for more Spelunky 2 guides.
from GamersHeroes http://www.gamersheroes.com/game-guides/where-to-use-the-golden-key-in-spelunky-2/