It's 9/9/2018 today, so it's like 9/9/9+9. That's the perfect moment for celebrating a Cirno Day!
I tried to make something light and cute for this Cirno day, but... The plot gone out of control (as usual with me) and turned out to this. Battles, broken kappas' dam, the serious treat to the Human Village, and so on... (Well, at least it's the strongest day after all.)
The name of this episode is a reference to two famous disaster movies: "Independence Day" and "The Day After Tomorrow". That's how youkai (fairy) attack on Gensokyo may lead to total destruction, if... Ah, I hope you've got the idea.
I've just imagined, Reimu, as everything resolved, is writing something like this: "Dear princess Celestia. Today I've learned an another big lesson of friendship. You might treat your duty as something more important than your friends, but ignoring them might cost you even more than you would expect. At least in Gensokyo it works like that, especially if your friend is 'strongest' fairy." Oh