There are a bunch of pieces of paper the you have to touch which completes a pic of what the dragon should look like.
You have to find all the pieces of the picture, so that you can open the secret entrance in the underground tunnel.
go to the underground tour
the picture on counterfeit island is a picture for when you go underground and you go on top of the ladder u fix the dragon the way it is on the picture
On Astro Knights islandThe dragon is at the bottom of the volcano on the Fire Planet (X-83 Y-20).On Counterfeit IslandThe Dragon Face lock is on the underground entrance to the Museum, and requires you to have all six pieces of the picture to open it.
In the Underground, go to the hanging light bulb and climb up the cord. Jump hard to the right to get the dragon picture piece.
Climb the extension cord in the archway to find the dragon picture piece. You will pass the ladder that leads to the underground entrance to the museum (for later). At the exit, you will meet the shady guy who tells you the painting is in danger.
Climb the wire from the light bulb in the arch, then jump hard to the right from the top.
There is no safe on Counterfeit Island. There is an underground hatch that has a Dragon Face lock on it.
You don't need a balloon to get the dragon picture piece from the underground - it is only an easy way if you haven't already gone into the museum. Climb ALL THE WAY UP on the cord in the underground arch. Jump VERY HARD to the right and you should get the picture piece.
a dragon
you have to find the pieces.
The main entrance is just to the left of the park where you arrive on the island. You will not be able to enter the museum until you have taken the Underground Tunnel Tour. At night, the secret underground entrance leads up into the supply room. You will need to open the Dragon Face lock. (see related question)