All MCU villains introduced so far have overlooked the deadliest, most silent weapon on Earth, which made its debut in Phase 1’s The Incredible Hulk. MCU heroes are constantly adapting to supervillains’ evil plans, which can range from political sabotage to the annihilation of half of all life in the universe. To accomplish those goals, MCU villains usually resort to developing, stealing, or copying powerful weapons, often closely connected to the heroes’ own abilities and origin stories.

Not every villain in the MCU seeks to kill. For instance, Kaecilius and Malekith wanted to plunge the universe into darkness, while Obadiah Stane and Darren Cross wanted to weaponize revolutionary technology. Still, most villains would have benefited from an efficient weapon that left no traces, if not to help them take over the world, then at least to help them defeat the heroes who opposed their plans. Some of them have tried to find that weapon in the Super Soldier serum, others in vibranium, and others in the Infinity Stones. What they failed to notice is that the MCU’s greatest weapon was always more accessible than it seemed.

The Incredible Hulk Proved That Bruce Banner’s Blood Is A Powerful Weapon

Hulk’s Blood Could Be The Most Effective Weapon In The MCU

In The Incredible Hulk, Bruce Banner accidentally cuts his finger while working at a soda bottling factory. A single drop of blood falls into a bottle, which gets delivered as normal. Eventually, a consumer (played by Stan Lee) drinks from the bottle, dying immediately afterward. Evidently, Bruce Banner’s Gamma-irradiated blood is deadly to regular humans, and all it has to do to kill a person is enter their body. If any MCU villain got their hands on Hulk’s blood, their targets could be dead before they even realize it.

General Ross, Emil Blonsky, and Samuel Stern understood the potential of Hulk’s physiology, but they focused on the effects of Gamma radiation on the modified Super Soldier serum in Bruce Banner’s body, which is the key to attaining Hulk-like transformations. Instead of fuel for their own power, Hulk’s blood could have been their ammunition. Of course, retrieving Hulk’s blood might be the most difficult part of the plan, but powerful villains like Abomination, Ultron, and Thanos could have achieved it, and ambitious criminals like Justin Hammer, Aldrich Killian, and Baron Zemo could have at least considered it.

She-Hulk: Attorney At Law Raises Questions About Hulk’s Blood

A Single Human Being Has Survived Contact With A Hulk’s Blood

Characters like Bruce Banner, Emil Blonsky, and Jennifer Walters gain powers when exposed to Gamma radiation because they’re genetically primed to it, either naturally or artificially. Samuel Sterns used Bruce Banner’s blood for his own experiments, and he must have secretly used it on himself at some point, which would explain why he mutated as soon as Banner’s blood entered his bloodstream during The Incredible Hulk‘s ending. In Captain America: Brave New World, Sterns may use his blood to prime other test subjects, including President Ross himself.

The only character to break this logic is Todd Phelps, who transformed into “HulkKing” with She-Hulk’s stolen blood during She-Hulk: Attorney At Law‘s finale. However, the reason why Todd achieved a Hulk transformation without dying might be because the events of the She-Hulk: Attorney At Law finale weren’t supposed to happen. Once Jennifer Walters rewrote reality, Todd Phelps’ experiment wouldn’t have worked, and he would have likely died a quick death, just like Stan Lee’s cameo character in The Incredible Hulk.