We now know that Batman dreams in IMAX, and that the most spectacular sequence in Zack Snyder's "Dawn of Justice" contains premonitions of what evil lurks in the upcoming "Justice League" movie. It's like something out of "Inception" with such tantalizing clues as the Omega symbol associated with DC god-villain Darkseid and the presence of his flying parademons. And the post-apocalyptic desert vibe seems straight out of "Mad Max: Fury Road."

In the dream, Batman seeks to find Kryptonite in a post apocalyptic world ruled by an oppressive Superman with a legion of soldiers and extraterrestrials that swoop down like the flying monkeys from "The Wizard of Oz." After duking it out, Batman gets captured and taken to a bunker, where he's betrayed by Superman.

'Batman v Superman: Dawn of Justice Desert Vista

"There are little Easter Eggs that get populated along the way," admitted production VFX supervisor John "DJ" DesJardin, who's worked with director Snyder since "Watchmen."

"What's that city he's looking at? It's really Gotham. And when you look behind Batman when he's [peering] out past camera, you can see Wayne Manor. And then if you look in the direction he's looking, you can see the remains of his glass house up on a hill. You can kind of piece together where the Omega symbol is (where the lake used to be where the Batcave was located down below)."

Shot on the Warner Bros. backlot, the sequence evolved into a trippy bit of phantasmagoria that links the DC universe with Batman's worst fears about Superman's God-like powers. The VFX was divided between Weta Digital and Double Negative and cleverly stitched together.

Batman V Superman: Dawn Of Justice

"We kept moving people around and putting dummies on the ground to be replaced. It's hard to match all those things up so we pieced the three sections together editorially to get a sense of the action and scope. We knew we had to cover it a certain way to do what I knew we were going to inevitably do, which was erase everybody out of the frame and keep Batman live as much as we could."

DesJardin also made great use of the 'enviro-cam" from "Man of Steel": a Canon EOS 5D mounted on a camera rig that captures a 360-degree panoramic perspective.

"The enviro-cam is a really neat way of capturing the entire set or location from a certain camera point of view, and I did that for each of technocrane start and end positions. There was a lot of dynamics going on that we had to respect and they all eventually get turned into CG people."

But because they could play with so much virtual world building, Desjardin's imagination ran wild.

"I told Zack and Damon let's add some more guys up on the wall and add more demons that come down. And then add some helicopters, including one that blows up a gun turret. With such a virtual clean slate, you can keep adding elements."