This promo pack was part of the stretch goals of the 2015 Best Treehouse Ever Kickstarter campaign for all backers that backed at least a single copy of the game. It includes:
Advanced Bonus Cards: 6 more Bonus Cards! They are also hidden goals but this time the higher you build your secret formations in your tree, the more points they are worth!
Advanced Game Changers: 4 more score modifier cards will create even more ways to play and some extra strategic decisions for end-of-round scoring!
Birdhouses: For this variant, each player receives a Birdhouse Card to use once per game. Discard your Birdhouse to reset your Balance Marker and get yourself out of a tough situation.