Resize potion spell?

[QUACK]

So I was getting resize potion spell x2 for free without spending ascended candles, I can't figure out how did I get it. My logic goes to some spirit that I've done, but I have no idea which seasonal spirits tho. Does anyone know how? I might want to get them again *if possible.

[Meowish]

You get random spells from doing the spirit tree, so there's no 100% fixed route on which spirit will give you that, it all depends on your luck.

[D:\side\]

Whenever you unlock a star in a reward tree (spirit friendship or anywhere else) you get a few spells of a random type.

I'm not sure there's a bias related to the type of spirit (e. g. season spirits giving season spells), but there might be. You can also see the "Blessings" page on the community wiki.