4. Superman Is Under The Influence Of Red Kryptonite
The Rumour: Another explanation for Superman's borderline-murderous attack against Batman is that he's under the influence of red Kryptonite. The theory posits that Lex Luthor and Batman work together to engineer a Kryptonite strain that can bring Superman under control (because green's not good enough?), but of course, the red Kryptonite just ends up boosting Supes' powers to dangerous levels, where he loses control of them. How Likely Is It?: 3/10. It's a ton more plausible than the aforementioned Bizarro theory, but considering that the movie already has green Kryptonite which can do a pretty damn good job of containing Superman itself, it seems overkill to start throwing the other variants of Kryptonite into the fray. There are worse things the movie could do to ignite fanboy ire, but at the same time, we just don't need this at all.