Hello. This is Hank Green for Truth or Fail coming back to you from a rather long hiatus which I'm sure has nothing to do with any other projects that I'm working on. But look, down the bottom here. You see that? That's me thinking about Truth or Fail. That way it says truth and this way it says fail. Thank you to Dan Brown for helping me design that. And that is what this is. This is Truth or Fail, a very simple YouTube game show in which I give you two facts, you click on the true one or you fail. This episode is about dinosaurs. That's a chicken, that's not a dinosaur or is it? The question is why. Why are we doing dinosaurs? Well dinosaurs, their bodies and all of the bodies of the prehistoric plant matter fell to bottom of the Earth and they coalesced and they became fossil fuels which have been in the news lately. This is, this is too much of a stretch. We're doing dinosaurs because dinosaurs are awesome. This episode was written by Adam Z. Brown. Let us begin now.

Fact one: The largest dinosaur ever to exist was the giant brachiosaurus.

OR

Fact two: The repenomamus was a giant prehistoric rat-like mammal that fed on dinosaurs.