@Background Pony #4FCA
 
Ah, so it’s a lot like Ghostbusters II with the good and bad slime, and Vigo.

So now my question is how Twilight’s lawyer and the Canterlot prosecutor would deal with the jury selection for her trial for conspiracy to commit murder and conspiracy to commit arson.

@Background Pony #0A96  

 
More accurate, emotional energy. Pinkie and Cheesie found the solution, they discovered that the moss can assimilate all sound, but is sensitive to emotional forces through sound - very similar to the changelings. The laughter itself was not enough, there must be a positive emotional force in the laughter itself. The happier you laugh, the stronger the effect will be on the moss which will thus weather. Happy laughter is the key. All sound will not work, even the most noisy (they tried!) And it is possible that sound with a negative feeling such as when crying or screaming, makes the moss grow faster. When Pinkie and Chessie discovered that they must make others laugh heartily and happily, the positive feeling in the sounds will thus make the moss wilt away.
 
This is surprisingly logical in itself.

She is so adorable with her tongue stuck out like that. She’s having so much fun solving the problem that you almost forget that Equestria is under existential threat.
 
Of course, this is Equestria, and “existential threat” means “it must be Tuesday,” so maybe she’s used to it.

Wait. Laughter? In a room where sound waves are assimilated by the moss? She should not be able to hear the laughter itself. It seems that Twilight did not yet realize it when she was busy with her solution orientation. She will jump in the air as soon as it sinks into her brain. Maybe the answer to the dilemma lies in laughter.

Fire solves everything!

Nerds can save the country, y’all

She gone THAT mad? :o xD

Nerd…

Twilight planning to burn down Equestria for the insurance money.

You need more fire. The giggling comes after you have enough fire. It’s your own giggling, btw.
 
Still not enough fire.
 
More. More. Moooore. Not enough. More!