Whooooa! Whatta trip! 
- —Doc Surf
Appearing in 1st story
Featured Characters:
- Avengers
- Captain America (Steve Rogers) (Merges with Hulk and Silver Surfer into Major Gamma and Captain Cosmos)
- Vision (Merges with Hulk and Valkyrie into the Hulkoid and Reaper)
- Scarlet Witch (Wanda Maximoff) (Merges with Doctor Strange and Namor the Sub-Mariner into Scarlet Strange and Imperius Hex)
- Thor (Odinson) (Merges with Namor the Sub-Mariner and Iron Man into Sturm Meister and Gadget)
- Iron Man (Tony Stark) (Merges with Thor and Valkyrie into Gadget and Eiserne Jungfrau)
- Defenders
- Namor the Sub-Mariner (Merges with Thor and Scarlet Witch into Sturm Meister and Imperius Hex)
- Doctor Strange (Stephen Strange) (Merges with Silver Surfer and Scarlet Witch into Doctor Surf and Scarlet Strange)
- Silver Surfer (Norrin Radd) (Merges with Doctor Strange and Captain America into Doctor Surf and Captain Cosmos)
- Valkyrie (Brunnhilde) (Merges with Vision and Iron Man into Reaper and Eiserne Jungfrau)
- Hulk (Bruce Banner) (Merges with Captain America and Vision into Major Gamma and the Hulkoid)
Supporting Characters:
Antagonists:
- Mephisto
- Heimdall
- Warriors Three
- Unbelievables (First appearance)
- Sha Wujing (First appearance)
- Vampire Vixen (First appearance)
- Devil Dawg (First appearance)
- Mighty Martian (First appearance)
- Sun Wukong
Other Characters:
- Heralds of Galactus (Mentioned)
- Agamotto (Mentioned)
- Ish'lzog (Mentioned)
- Varmint (First appearance)
- Viktor Vile (First appearance)
- Nina Nova (First appearance)
- Cyrus Black
- Comet Capone (First appearance)
- Diablo (Esteban de Ablo)
- Doctor "Doc" Surf (First appearance)
- Major Gamma (Name revealed)
- The Hulkoid (First appearance)
- Scarlet Strange (First appearance)
- Sturm Meister (First appearance)
- Reaper (First appearance)
- Imperius Hex (Name revealed)
- Gadget (First appearance)
- Eiserne Jungfrau (First appearance)
- Captain Cosmos (First appearance)
- Three unidentified amalgamations (First appearance)
Races and Species:
- Humans
- Atlantean-Human Hybrids
- Cosmic Beings
- Synthezoids
- Zenn-Lavians
- Demons
- Asgardians
- Vanir
- Gods (Mentioned)
- Dogs
- Kraken (Invoked)
- Vampires
- Martians
- Xian
- Bats (Illusion or holographic simulation)
- Serpents (Mentioned)
Locations:
- Earth-616
- Earth
- Negative Zone (Mentioned)
- Space
- Mephisto's Realm
- Asgard
- Incredibly Secret HQ of the Unbelievables (First appearance)
Items:
- Fantastic Four Uniforms
- Captain America's Uniform and Shield
- Negative Zone Portal
- Cask of Cyttorak and Infernal Ichor of Ish'lzog
- Cloak of Levitation and Eye of Agamotto
- Power Cosmic
- Scarlet Witch's Suit
- Orb of Agamotto
- Hellfire
- Mjolnir
- Dragonfang
- Hofund
- Hridgandr
- Fimbuldraugr
- Uru (Mentioned)
- Iron Man Armor Model 4
- Spider-Man's Suit and Web-Shooters
- Daredevil's Suit and Billy Club
- Ruyi Jingu Bang
- Diablo's Tarot Cards
- Trident of Neptune
Vehicles:
Synopsis for 1st story
- Synopsis not yet written
Solicit Synopsis
As the chaos and madness continues to spread, the Avengers and the Defenders find themselves confronted by the most unlikely characters in Marvel history! Would you believe – THE UNBELIEVABLES?