Despite his reputation as the strongest superhero in the Marvel Universe, the Doctor Strange, the power to breathe underwater, and a powerful healing factor that can actually bring him back from the dead.
One ability the Hulk possesses that was not provided by Banner is his ability to exist in a sort of dream-like “mindscape” whenever he isn’t active in the physical world. Because Banner has multiple personalities, with each personality manifesting as a different Hulk, they can all interact and even have conversations with each other in Banner’s mind. Banner himself can have “mental chats” with the Hulks – all thanks to a magical spell cast by Doctor Strange.
Prior to Strange’s intervention, Banner and Hulk could communicate with each other, but in a much more limited way. Writer Peter David showed the two leaving messages for each other on mirrors or even arguing each other as the Hulk transformed back into Banner (or vice versa). However, all of this took on an entirely new dimension in The Incredible Hulk #370 when Hulk encountered Doctor Strange.
At the time, the dominant Hulk was a grey-skinned monster who liked to go by “Joe Fixit.” Somewhat less powerful than the Green Hulk, Joe was much more intelligent and transformed into the Hulk automatically at night. While he initially hated Banner, the two personalities achieved a tense understanding, which was put to the test when Doctor Strange had Banner ask the Hulk for his help in a case. To facilitate the discussion, Strange cast a spell that allowed Banner and Hulk to meet on a mental plane in their shared consciousness.
The mindscape looked like one of the weird dimensions Strange traveled through, and even contained symbolic representations of Hulk’s fractured psyche – including a locked door that Joe and Bruce had unconsciously trapped the Green Hulk behind. Eventually, this door was breached, allowing the Green Hulk to escape (and manifest in the physical world). Most surprisingly, however, this “mindscape” lingered even after Hulk’s adventure with Doctor Strange was completed and exists to this very day.
While the mindscape was originally intended to let Banner have a “conference call” with the Grey Hulk, it soon became crowded with many of Banner’s other personalities. These included the savage green Hulk who fought the grey Hulk for dominance. Later, the green and grey Hulks merged with Banner’s psyche to create a new personality – the so-called “Professor” or “Smart Hulk.” While this persona thought he was Bruce Banner, he later found himself in the mindscape once Banner’s human personality reasserted itself.
Ironically, some of the Hulks who appeared in the mindscape never manifested in the real world. Chief among these was one of the original “Devil Hulks” who appeared as a yellow, reptilian creature who tried to seduce Banner into giving up control of the physical body by constructing an idealistic fantasy world within the mindscape where Banner was a respected scientist with a happy family life. When Banner’s other Hulk personalities resurfaced, however, he realized the truth and rejected the offer.
Most recently, Banner has been having conversations with a new “Devil Hulk” (actually a more paternal Hulk that Bruce created to be a father figure), Joe Fixit (who now manifests in Bruce’s human body), and the classic green Hulk (whom Banner has actually started developing some sympathy for). Their “conference calls” are a startling representation of Banner’s fractured psyche, but also help establish the nature of Banner’s different Hulk personalities and how they relate to him. Thus, what may have been a spell of convenience for Doctor Strange has since become one of the primary means of communication between Bruce Banner and his different Hulk selves.
