Use the Blue Tulip to help the man in the Dos Cactos with a big head. He said only the rare Blue Tulip can regain his normal head. Give the Blue Tulip to him and his head will return to normal size and he doesn’t have anything to give you in return but a piece of the map to the hideout.
How to get the Blue Tulip
Use the key to enter the mine to the right. Walk to the right and jump into the mine cart. This will start a long mine cart ride. During the ride, all you need to do is wait for the signal flags to appear and then click on them to shoot them. When you do the track will correct itself so that you avoid some nasty obstacles in your way. After several of the signals, you’ll arrive at the end of the mine track. Jump up onto the hill and you’ll find a Blue Tulip.