The hidden Color Dungeon was just one of the many new features that were placed in the DX version to make it more appealing for the fans to buy. After all, who wants a game that's just the same as one that they already have even if it is in color...(uhhh...bad question!)? The Color Dungeon can only be accessed in the DX version of Link's Awakening and can only be entered while the gamepak is in the Gameboy Color or Gameboy Advance.
If you would like to know how the heck to even find the dungeon rather than me just telling you, you will have to wait until after the completing the third dungeon and have the Pegasus Boots. Head over to the library and hit the back most bookcase (LttP rip-off!). A book will drop down. When you read it it says:
The New World of Color under the 5 Gravestones
3(UP) 4(RIGHT) 5(UP)
2(LEFT) 1(DOWN)
Head over to the Cemetary's southeast corner where you will find 5 gravestones that are arranged in the order of that diagram. Follow the directions! When you push the fifth one up, it will reveal a secret passage.
A few notes about the entering of the Color Dungeon and actually doing it. The Color Dungeon is NOT easy. It is very easy to die and it is highly recommended that you go in with some of Crazy Tracy's Elixer and when you run out to go get you some more. Next, if you are having difficulties entering the dungeon and you have followed the rules I've already put up (DX version in GBC or GBA), then take note of this rule. Have you already started a dungeon that you have not defeated the boss in? If the answer is "Yes" go back and complete that dungeon. You cannot access it half way through completing a dungeon.
The first room you enter you will meet two skeletons who have riddles for you. :P No brainers. Just answer which is wearing what color. In the next room you will the Camo Goblins. Make sure to tackle these guys one at a time. Approach their color very slowly and when they start moving, wait until they are below you before moving and turning around to swing at where you just stood. If you did it right, they are easily killed.
Going right and you will enter a room that houses the compass. To complete the puzzle simply hit the two switches in the northwest and southeast corners. Before leaving this room, bomb the south wall for a wonderful surprise! Going to the right in the previous room, ignore the bomb putter as best as you can. Try and equip the feather and use it where you can. These tiles will make you bounce and if you hit a red one, it disappears making a pit that you are likely to fall through if you aren't careful.
In the room to the right hit the Karakoro and pick them up and toss them into the holes of their color (careful, those holes are pits!) to receive the Stone Beak. First you will want to go up. Ignore the Bone Putters and carefully cross the tiled floor. In the next room there is another switch puzzle. Hit the switch in the northwest corner twice and the switch in the southeast corner once to receive a small key. Go right and kill the Camo Goblins. Use the small key on the door.
Guardian: Buzz Blob
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Do not hit this monster when its in the shape of the smaller Buzz Blobs around Koholint! Dust it with some magic powder and hit it with your sword while it's just a blob. If you run out of powder, a fairy will come to the rescue!
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After Buzz Blob is defeated, go left and receive the Nightmare Key. Head back down to the room with the Karakoros and go down. Kill the Camo Goblins and go left and get the chest that contains a small key. Go up. (Here's a trick for the tiles, if there is a pot in the room, pick it up and walk across the tiles and you won't hop and they won't turn a different color!) Open the looked door and go up.
Guardian: Dekudon
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Your shield will be useless in here. Instead, equip the feather and when Dekudon jumps to send a rain of rocks down on you, jump to keep from being stunned and an easier target. Quickly attack Dekudon before he starts doing this attack again.
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When he is dead, go left. Remember the trick I gave you? There is a pot in the southeast corner. Pick it up and walk to the other pot in the room. Smash that one and lift the other and push the button and use this pot to walk to the north door. Kill all the Gels in this room to receive the map. Go right and put the four Karakoros into their appropriate holes to receive a small key. Go back to the tile room and take a left.
Yet another switch room. Don't be fooled by this puzzle. It's actually alot easier than it appears. Just hit the North, East, West, and South switches that were the original reds!. The door will then open and you can go up. Use the key in this room to go left.
In this room if you have any throwing object, use it to hit the switch, however, if you don't, just walk over, hit the switch and walk back (you can stand on the pegs, remember). Unlock the door and go up.
Nightmare: D. Poon
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This boss is probably the most difficult out of any of the bosses you will find in the game. D. Poon will start off by giving you a clue about what the colors of its body means...to itself! Whenever you hit it with your sword, be prepared to be sent bounded back. It's best to have yourself against a wall and hit D. Poon with your back against that wall so that you can lay in a smack load of hits and still remain within reach since you won't be bounced back that far. Watch for things flying around and don't take any unneccessary chances. If D. Poon goes back from Red to Blue because you were being cautious, so be it. It's better than having to redo everything all over again.
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You Receive: Red Tunic or Blue Tunic. (You can always come back to this room in the future if you change your mind, but you can never get your Green Tunic back! When you take the Tunic, either the Guardian Acorns or the Pieces of Power will disappear from the game according to the Tunic type. -Having the Tunic on is equal to those items so don't think you can try for doubling it!)