5. Jax-Ur Is Lex
The evil doctor Jax-Ur who painfully operates on Kal-El while on Zods ship presents a confusing plot hole. Although its poorly represented in the film, its assumed he extracted the Growth Codex from Kal, despite Zod not realising it was in him at this point. A more playful (or pernickety) hole is that Jax isn't just a minor Superman villain, but also the biggest of them all. Jax is played by Mackenzie Gray who, like Adams, isnt new to Superman, having appeared in an episode of Smallville previously, playing a clone of Lex Luthor. But even that isnt the end of Grays Superman involvement. Five years before he became Kal-Els most notorious enemy hed already appeared in the series as Alistair Kreig, a sadistic doctor who worked with Luthor on Dalek-esque experiments. I guess he was always destined to play bit parts in Clark Kents adventures.
4. Keep Calm And Call Batman
Pretty much every Easter Egg we've listed so far can be picked up through the films run-time, but theres little way you could have spotted this next one, to the extent where even Zack Snyder himself admits its impossible. You might even have to stop the movie to see it, he says about a reference he had little involvement in. Double Negative, a special effects company who worked on the film, inserted their own version of the irritating poster craze - Keep Calm and Call Batman - into the final fight. Ironically placed, I somehow doubt his bat caller would have helped against Zods newly acquired heat vision. Unlike the Wayne Enterprises satellite in the same fight, this in-joke is purely referencing the character, its role in the future incidental; Double Negative did the visual effects for Christopher Nolan's Dark Knight Trilogy and this being so secret is clearly them honouring the previous big DC movies.