Now to find someone who wants this nearly useless Water Pistol? Oh yeah - the Fisherman likes those, doesn't he? Does he?!. She's in the Rowdy Rainforest, so set your controls for a world with some jungle on it, and go tracking the Tracker! She should be wandering around somewhere, holding a Water Pistol! Trade her your Dinosaur Tooth, and get a new gun in the process! Once you have her Dinosaur Tooth, it's time to trade it to someone who really wants it: The Dino Tracker. She will NOT be marked by a quest marker, so just keep looking around for wandering Jewel Thieves carrying teeth. Next, it's off to the Crystal Crags to find the elusive Jewel Thief who will take that Red Crystal and give you a Dinosaur Tooth for it.

In exchange, she'll give you a Red Crystal. Once you've done that, she'll want to trade you for a Pumpkin Head (which you can also find in the Weird Woods). She will ask you to place a Cauldron (found in the Weird Woods) and two different kinds of glowing Cave Mushrooms (found in Cave Systems or in the Chemistry Lab Brick Build) nearby. Next, go to the Lawless Lagoon and seek the Spooky Girl standing by some lab equipment (Try the Galactic Coordinates 163-193-103/D at X:-59.526, Y:27.072, Z:26.489).

The latter can be found on Harry-Mulligan-892/F at X:-14.41, Y:26.78, Z:-50.08) After this, she should be available to spawn in the swamps. Another is to build a campfire site for ghost stories. You'll have to place some charred flowers, gravestones and a bunch of iron fences, all of which can be found in the Weird Woods. (One beginning task is rebuilding her garden. To start, you'll need to Discover the Spooky Girl in her native Weird Woods and complete one of her tasks. All credit goes to gandalfwhi40 for finding this:

Update: This is pulled off of the Lego Worlds Wiki page.

How to get the dragon in lego worlds