Just in time for Winter (in the northern parts of the world, anyway): Snow!
Like Ruins, the Snow cards are mixed together in a Supply pile (there are 4 Fine Powders for every 3 Ices and 3 Packed Snows) and included in the Supply whenever there's a Frost in the Kingdom. As you can see, they're self-disposing with a minor inconvenience, almost an anti-Ruin. They also don't stay trashed, so the quick distribution and disposal won't run down the pile.
Of course, a Ruins-variant needs cards to distribute it, so on to the Frost cards:
First, the card that started it all: A junker that distributes Snow but likes it. Despite the Sea Hag-type topdeck attack, Snow is weak enough junk that it shouldn't be too punishing. In particular, the pin that necessitated Sea Hag's discard clause is likely impossible due to both the fact that all Snow cards draw (Fine Powder in particular is good at clearing out Snow cards in bulk) and the fact that Snow Queen's self-junking makes them hard to chain. I went back and forth on whether to make Snow Queen's gain $2 or $3 per Snow, but $3 seemed to make it too easy to gain Provinces. The gain is mandatory, but you can always discard nothing and gain another Snow.
Now, a non-attack card (very mild pseudo-attack aside) with an on-gain Snow ability. It has to cost $4 to avoid too many being bought in the opening. It provides some mild sifting with a bonus for discarding Snow cards (or Action cards that collide with it). Do you gain a Snow to avoid having to discard a useful card, and potentially get the +1VP?
Finally, Winter is coming with the Northern Lake. As soon as the first Province is bought, the lake effect brings the Snow on everyone. Do you trigger the blizzard early, hoping you can weather it better than your opponents?
One theme with these cards is that the Snow falls on everyone: The question is how well you can deal with it.