The Petrichor: Collector's Edition Kickstarter campaign included several new promo items that will be bundled and sold as a lot to allow for more variety in Petrichor.
The eight tiles are:
Alfalfa Tile
Biodome Tile
Blackberry Tile (comes with 6 bramble tokens)
Cloudberry Tile (comes with 1 growth token)
Snapdragon Tile (comes with 3 bloom tokens)
Sunflower Tile (comes with 5 sunshine tokens)
Venus Flytrap Tile (comes with 4 fly tokens)
Volcano Tile (comes with 1 control token)
Other promos:
Forecast Cards (4 cards: Forecast #21-24)
Extreme Weather Events (8 cards)
Terrain Objects (4 wooden pieces, with stickers for both sides)
A player aid card with rules for Extreme Weather Events on one side and Terrain Objects on the other side
Also called 'Petrichor CE Promos'
Rules for these promos can be found on:
English: http://mighty-boards.com/petrichor
German: http://schwerkraft-verlag.de/downloads/petrichor
or in the Petrichor: Collector's Edition rule book.