Randy was panicking at what to do.

Dipper:Hello, Ninja.

Randy:Wha-I'm not the...why would you think that?

He noticed the Ninjanomicon and mask were on the ground. Randy quickly pulled Dipper into the bathroom.

Randy:Okay, fine. I'm The Ninja. But, you cannot, I repeat, CANNOT tell ANYONE.

Dipper:Okay. Noted.

The two exited the bathroom, only to see Soos, Wendy, Mabel, and even Howard.

Randy:You heard of that, right?

Wendy:Yep. Don't worry, your secret is safe with us.

Randy:(Sigh of relief) Oh thank cheese.

Randy looked around.

Randy:Think we can discuss things somewhere more private?

The Pines Twins brought Randy and Howard upstairs.

Dipper:Yeah, Mabel told me about that fight with the gnomes.

Randy:Can you blame me? I've never fought anything like that.

Dipper:Well, I got something that could prepare you if you fight anything else like that while you're here.

Dipper pulled out Journal #3.

Howard:Oh great. You have a boring mystery book too.

Randy opened the journal, and was surprised at the number of monsters and anomalies that reside in Gravity Falls.

Randy:Living wax figures, crystals that change the size of things, zombies. You know what, I take it back. This town is SOOOO not boring. Well, as long as we're sharing info, I think you should get to know some knowledge about what I go up against.

He brought out the Ninjanomicon and opened it.

Randy:Though to give a heads up, this may feel weird.

Dipper:Why would this-

He  was interrupted by them being shloomped into the book.

Mabel:Uhhh, what just happened?

Howard:Eh that book is just giving them ancient ninja wisdom. They should be out in a few minutes.

Meanwhile, inside the nomicon, Dipper screamed as he and Randy fell. Once they landed, Dipper was still screaming, but quickly  stopped.

Dipper:Okay, that was weird.

Randy:Eh,  after a few times, you get used it. Welcome to the Ninjanomicon. The  book that contains all the knowledge and wisdom from the previous ninjas  over the last 800 years.

Dipper was amazed by the book.

Dipper:So what made you think my sister and I could be trusted?

Randy:Well, the Nomicon said this.

The text appeared again.

When facing an unusual enemy,

you must seek help from an unusual ally

Dipper saw an illustration of a certain foe of Randy's.

Dipper:Who's that ugly guy?

Randy:That would be The Sorcerer. The first ninja imprisoned him 800 years ago. He uses his stank-

Dipper:Stank?

Randy:Some  evil funk magic. Anyway, he uses it to possess the vulnerable, using  that which they hold most dear. Which turns them into monsters. He uses  the chaos the monsters create to gain enough power to escape. But he  never can, 'cause guess who always stops him?!

Dipper:How do you turn the people back?

Randy:I gotta destroy said object they hold most dear.

Dipper's train of thought was interrupted when he had a sudden realization.

Dipper:You said you guys are from Norrisville, right?

Randy:Yeah?

Dipper:We had another Norrisville guy earlier. Some guy named "McFist" apparently showed up earlier.

Randy was shocked.

Randy:Wait, short guy, brown suit, long mustache, robot arm?

Dipper:Yeah?

The two were suddenly shloomped out.

Randy:McFist is in town?!

Dipper:Judging by your reaction, I'm guessing he's evil?

Randy:Of course he is!

Dipper:Yeah, that doesn't surprise me. I mean with a name like Hannibal McFist, how can you not be evil?

Suddenly, loud crashing and screaming was heard from downstairs.

Soos:Uh dudes, you might want to come and see this...

Randy pulled out his mask.

Randy:Looks like its Ninja-o-clock!

Dipper:That is the dumbest catchphrase I have ever heard.

Howard:Thank you!