Split personality of the Hulk. Found this:
* Gray Hulk/Joe Fixit - The Gray Hulk (though possibly not the original) worked for a time as a Las Vegas enforcer called "Joe Fixit". The Gray Hulk has average intelligence, although he occasionally displays knowledge and intellectual ability normally associated with Banner. He is cunning, crafty, hedonistic, arrogant, and distant, with a hidden conscience.
In most of his Las Vegas appearances, he appears only at night. According to the Leader, the Gray Hulk persona is strongest during the night of the new moon and weakest during the full moon. This aversion to sun/moon light vanished when the Gray Hulk's night-induced transformation trigger was later removed.
Although he is the smallest of the Hulks, the Gray Hulk towers over the average human. He prefers to dress in tailored suits.
Joe Fixit's base strength level is also the lowest of the three primary Hulk incarnations. While in a functionally calm emotional state, Joe Fixit is able to lift about 70 tons.