4. Batman's Stash
Batman is always one step ahead of everyone, including his fellow members of the Justice League. While Batman v Superman will seemingly be the movie which introduces those characters to the world, you have to imagine that the Caped Crusader is already well aware of their existence. Whether this was at the end of the movie or an after-credits scene, revealing that he has ways of taking them all down would just be insanely cool. The scene above comes from Forever Evil, but his stash of weapons was first revealed in an issue of Justice League. It's been reported that the armoured Batsuit featured in the Comic-Con teaser trailer will be laced with Kryptonite, so Batman is clearly aware of that weakness already. Even if there's never any sort of pay off with an Easter Egg such as the one above, teasing Batman v Justice League is a way to get moviegoers talking, that's for sure!