This is one of two add-on expansion packs known as "Adventure Packs." I got this FREE with a Toys'R'US promotion for buying the Starter Pack. The other "Adventure Pack" is the one called "Pirate Seas."
This Adventure Pack features: The Crypt (Special Level), Healing Elixir and Time Twister (2 Magic Items), and Ghost Roaster (Skylander). It looks awesome and being free I can't complain...it was actually a cool promo seeing how this was 2 days before Halloween!
The video covers most of the details, if you've got questions just leave a comment and I'll do my best to help you out.
Edit 11/9/2011: I wanted to get Ghost Roaster's stats here, even though I created the new post with he and Terrafin's statistics. This will just be another source
Ghost Roaster (Undead)