I never noticed that the flaaffy is using the electricity emanating from its tale to power a cord, which I presume goes to the lights on the Christmas tree. Pretty coooooool!
That doesn’t happen often. All the cards I had in mind are already named above by OP him/herself or others. I actually gave those suggestions on reddit recently (here the quote):
The only other card that personally gives me Christmas vibes is this Arcanine, even though it has nothing to do with neither Christmas nor snow. The flame-sparkles from Arcanine aligning with the pine-tree just reminds me of a Christmas tree with Christmas balls.