Pinkie Pie tells ponies "Never ever break a Pinkie Promise!" And when Applejack did that one time she yelled like a demon. But, when she Pinkie Promised to help Twilight with reorganizing her Library. She ends up breaking the Pinkie Promise and helps the Cakes foalsit the twins. Twilight tells Pinkie Pie what she has done and calls her something that she can't quite comprehend.

Hypocrite. What is a hypocrite? Can you eat it? Can you smell it? Can you do anything with it? Pinkie really wanted to know what the word hypocrite means.

So, she goes on a journey. A journey to the Ancient Infinity Word Definition Scroll in the mountains of the Crystal Empire.

It'll be dangerous. It'll be restless. It'll be...the greatest journey of all time! Yep. Time to find out what a hypocrite is, and if she is one.