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- Abra
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- Alpha Blogg
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- AlterEgo
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- Amon
- Amon-Gorloth
- Amon (Devilman)
- Ampulex Compressa Giganteus
- Amun
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- AncientKazemon
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- Ancient Spirits of Evil
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- Angelique
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- Anubis (Resident Evil)
- Ao Oni
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- Apotheosis
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- Aptom
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- Armus
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- Asad
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- Ashigaru
- Ashley Fallon
- Ashrah
- Ashwinder (Cinzal)
- Asphyxia
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- Astaroth
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- Astral Spirits (H.G. Wells)
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- Azog the Defiler
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- B'gnu-Thun
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- Bandit
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- Baragon
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- Barbara Streisand (South Park)
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- Barugon
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- Bast
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- Battra
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- Beast (Marvel)
- Beast (SSSS)
- Beast Man
- Beast of Bodmin
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- Beast of Gévaudan
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- Bebop
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- Beetlejuice
- Behemoth
- Behemoth (Kingdom Hearts)
- Beholder
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- Berk
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- Blackness from the Stars
- Bladderhorn
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- Blastoise
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- Bloat
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- Bloblet
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- Bloggling
- Blood Fiend
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- Bloodsucker (Silent Hill)
- Bloodsucker (disambiguation)
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- Boo Block
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