WARNING: This contains spoilers for The Batman.
The Batman introduced several iconic Batman villains and set up exciting possibilities for the future, but one theory about how Bane had been teased in the movie was just debunked. Despite having the Riddler as the main antagonist, The Batman also saw Carmine Falcone, The Penguin, and Catwoman as important parts of Batman's story. On top of that, the movie also introduced the Joker, played by Barry Keoghan. According to many theories and speculations, however, The Batman was trying to lay out the path for a sixth Batman villain.
Towards the end of the film, when Batman is going up against the Riddler-inspired shooters, the hero ends up getting knocked down. To get himself up, Batman had to inject himself with some sort of green liquid, which prompted him to quickly get back into action, now angrier and more violent. This was enough to spawn and popularize a theory that the liquid Batman injected himself with was Bane's Venom. In the comics, Venom is a highly addictive chemical compound that serves to amplify the user's physical capabilities, and it's what Bane uses to transform himself into a nearly unbeatable foe in terms of sheer strength.
Related: Why Alfred And Bruce's Relationship Is So Different In The Batman
As much as the theory that The Batman was nodding to Bane’s Venom during that scene looked like it made sense, The Art of The Batman book just proved it was wrong. According to the official material, the liquid with which Batman injects himself was nothing more than adrenaline for when “he himself of somebody might need”. There’s no mention of the term Venom nor to any other Bane-related elements such as Santa Prisca. Essentially, this Batman was just wary enough
Read more on screenrant.com