The original Hulk was shown as grey and average in intelligence who roamed aimlessly and became annoyed at "puny" humans who took him for a dangerous monster. Shortly after becoming the Hulk, his transformation continued turning him green, coinciding with him beginning to display primitive speech, and by "Incredible Hulk" #4 radiation treatments gave Banner's mind complete control of the Hulk's body. While Banner relished his indestructibility and power, he was quick to anger and more aggressive in his Hulk form, and, while he became known as a hero alongside the Avengers, his increasing paranoia caused him to leave the group, believing he would never be trusted.