Ben 10 Fan Fiction Wiki
Ben 10 Fan Fiction Wiki
Big Boo
Brandon 10 - Big Boo.png
General Information
Species Pesadilla
Home World The Nightmare Realm
DNA source Ghost Brandon
Body Spirit
Alternate Counterparts Ghost Brandon
Powers and Abilities
Abilities Intangibility
Nightmare Implication
Dark Energy Manipulation
First Appearance Theater Terror

Big Boo is an alien transformation from the show, Brandon 10.


Big Boo takes the appearance of a short, blue being made up of four layers of ragged skin; the top layer being his head, the second being his torso, the third being his waist and the bottom layer being his tail. He has claws on his arms and no visible mouth. He also has bubble-like green eyes. The Omnitrix Symbol is on his chest.

Transformation Sequence

Brandon's eyes then shift to become more triangular and greener. Brandon's facial skin then loosens and turns slightly blue. More and more layers are then created as the skin is now fully blue. His hands then turn into dark claw-like arms. After cycling around in a circle, Big Boo appears in a pose.

Powers and Abilities

Big Boo has the ability of flight as well as invisibility and intangibility. He can also remove dark energy from beneath his skin and use it in a multitude of ways. However, the main use is typically as a way of extracting nightmares from his opponents and using it against them.

Big Boo can also use his claws as a slash attack.


Big Boo can be weakened by large amounts of light as well as certain chemicals, which can be used to cancel out his invisibility. Certain energy frequencies can also cancel out his phasing abilities as seen in Brawl. Electrical attacks also weaken Big Boo when he is caught off guard or captured.


Original Series


Video Games

Online Games



  • He is the first ghost and flight alien in Brandon 10.
  • In The Original Series, Big Boo was still used after he had lost control to Ghost Brandon which technically made him the 11th alien in The Original Ten.
    • However, this failed to make much sense so it was later changed so that Big Boo was still in the Original Ten and Twisty was made the first additional alien.
  • Big Boo is the only alien apart of The Original Ten who didn't get a short.


Brandon 10
Main Characters in The Original Series
Brandon 10 | Coco
Supporting Characters in The Original Series
Kayla | Sophia
Villains in The Original Series
The Conqueror | The Creator | The Mutater | The Sorceress
Aliens in The Original Series
Freezefire | Ro-Warasaur | Wildpup | Big Boo | Slime Shot | Gasadactyl | Angler Fish | Snow Bear | Virus | Aqualad
Additional Aliens in The Original Series
Twisty | Beastie | Rocks