Metazoo

MetaZoo: Cryptid Nation is an upcoming trading card game created by Michael Waddell, currently in a fundraising phase. The first card set will feature U.S.A. cryptids, called "Beasties," including Bigfoot, Mothman, the Jersey Devil, the Flatwoods Monster, and Indrid Cold. Its core mechanic, and the origin of the name "MetaZoo," is explained by the developers:
“... the strength of your Beasties and Spells are impacted by the environment you play in. Playing on a rainy day? Your Water Beasties get a power boost. Player near an open fire while trying to keep warm as it snows outside? Your Flame Spells are now twice as powerful, but watch out... the Snow outside not only boosts the strength of your opponent's Snow Beasties, but also makes some of them invisible (unable to be directly attacked).