What Happened To Every Version Of The Hulk?

Created by the Impossible Man's genius idea to join the Hulk and the Red Hulk together, the Compound Hulk is perhaps the most unpredictable of all the various Hulks, because it requires two characters who categorically do not get on to work together.

While the pair eventually set aside their differences to fight the villain the Impossible Man has set them against, the whole thing seems to be more mentally traumatising instead of team building, leading the pair to agree to never speak of their time conjoined ever again. It does make for a cool looking Hulk though, so there it's not all bad.