Snowtide Event Cards is a mini-expansion for Oddball Aeronauts and/or for Oddball Aeronauts 2, which contains 5 cards. It was added as a funding reward to all backers of the Oddball Aeronauts 2: Double the Trouble Kickstarter campaign in 2014. The 5 cards are: Mermaids, Gift Ficklers, Icemordbergs, the Snowfather, and the Snow Maker.
From the Kickstarter page:
"Swaying and spinning their way down to this Kickstarter through the myriad flakes of snow, the Gift Ficklers have brought 5 Snowtide Event Cards (one including the Snowfather himself!)."