Page 232 – From the Zebra’s Mouth

And the truth comes out.

Zecora: The Poison Joke cure has been my life’s work. For seven years now, I’ve been forced to lurk. I’m very close, but not there yet, so I need one last data set.

Fluttershy: Are you… also affected by Poison Joke, Zecora?

DM: She simply nods.

Pinkie Pie: What about all the info I got? That stuff about the ponies in Ponyville disappearing or going mad?

Zecora: Yes, those ponies had to endure the effects of my partial cure. Every pony I talked to would mock me or flee. So I conducted experiments secretly.

Twilight Sparkle: So you WERE using ponies as test subjects!

Pinkie Pie: I WAS RIGHT ALL ALONG!!