After the Friendship Games, Principal Celestia receives a phone call from her friend, Irving Slimovitz of Norrisville High. They, both having dealt with crazy, unexplainable things on both sides, decide to host a Inter-School Unit Project, or just a really-big meet up between the two schools.

Except Slimovitz didn't mention that Norrisville High is attacked by Monsters and/or Killer Robots on a daily basis...and is saved by The Ninja on the exact same basis. And Celestia didn't mention that her school hosts a portal to an alternate reality full of colorful ponies, and her students are their counterparts.

Yeah...to say things are going to go south...is saying it lightly. It's nothing a Ninja can't handle, though...
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A Randy Cunningham, Ninth-Grade Ninja crossover, set a school year after the Series ends. Will have swearing, a little bruising, and lots of Ninja on monster/robot action.