The Oni
Ao Oni Movie Model
Intro Roaring
Type Giant Chaser
Signs of nearing Japanese voices and growling sounds from the movie

TF2 voice lines which can mimic the voices of others to fool its victims

Origin Ao Oni
Map(s) Special boss
Theme song Ao Oni chase (Movie)
Partners Blockman Oni
Stunnable? No

Ao Oni is a boss on Slender Fortress.


Ao Oni is a blue and tall creature with a large head. Its face resembles the one of a normal human being, except for his big eyes having one of them bigger than the other, featureless body. It always has the same bemused expression on its face. The back of the Oni is black, suggesting dim lighting or hair.

Surprisingly, the Oni sports no teeth but it seems to be able to open its mouth unusually large, almost half the size of its head. The Oni also has heat vision which lets it see living things through body heat.

In Slender FortressEdit

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  • The model of Ao Oni utilized from the movie, since the old model has been deleted until it was reuploaded.