“The detonator!” shouts Dipper.

Mabel takes a deep breath and pushes down the plunger.

BOOM!

There’s a tremendous explosion and rocks fall around them in a calamitous debris slide.

Mabel, Dipper, and Blendin hit the ground and cover their heads.

As the rocks settle, they look up.

“We’ve done it!” says Dipper. “The path is sealed!”

“Yay!” says Mabel. “We blocked out that creepy prospector!”

“I heard that,” says Jugsley from the other side of the debris. “Dagnabbit! Flibberjibbet!”

Blendin and the twins high-five.

“Take that, you bearded lunatic!” says Dipper.

“Um, Dipper,” says Mabel. “The ground hasn’t stopped shaking.”

She, Dipper, and Blendin pause.

The ground is trembling.

“Did we cause an earthquake or something?” asks Dipper.

“Oh, no!” shouts Blendin. “Everyone hold on to something!”

The floor cracks and black liquid shoots out like a geyser. It hits the ceiling above and breaks a hole through it.

“Hooray! We’ve struck dirty water!” exclaims Mabel.

“It’s oil, Mabel!” says Dipper, grinning. “And it just created a way out!”

They climb to the surface and survey their claim.

“Do you realize what this means?” yells Blendin. “We’re oil rich! The best kind of rich! We don’t need the treasure anymore! And I can wear a cowboy hat and call myself something like Big Hoss and people will be too intimidated to make fun of me!”

The twins cheer.

A couple of hours later, Blendin and the twins have worked out an arrangement: Blendin will stay in the past to monitor the oil-drilling operations and will put a portion of the money aside for Dipper and Mabel. He’ll bury it in the ground, and when they get to the future, they can dig up their profits. The twins think it’s a great idea and say good-bye to Blendin. Dipper pulls the time tape, and they flash back to the future, ready to claim their reward. But something seems amiss. Gravity Falls doesn’t look exactly like Gravity Falls anymore. The sky has a dark-red apocalyptic color. There are bars on every window and graffiti on every wall. It looks like a war-torn nightmare. Dipper and Mabel are uneasy.

“Dipper, what happened to our home?” asks Mabel.

They stumble backward and discover that the statue of Nathaniel Northwest has been replaced with one of Toby Determined.

Dipper and Mabel gasp.

“Mabel, read the statue’s inscription,” says Dipper, stepping forward.

“This is horrible!” says Mabel.

“It’s okay, we can undo this Toby-geddon!” says Dipper. He pulls out the time tape but is completely horrorstruck as he discovers that oil has gotten in its circuits and it’s broken. The present is now permanent.

Looks like for them, this reality is…

THE END.