Nightmare is outright called "Shadow Freddy" in the game files. In "Hide and Seek", the third story in the sixth book in the Fazbear Frights series, Shadow Bonnie is the antagonist and appears in the protagonist's dream as a monster with sharp teeth and claws.

Is nightmare the nightmare version of Shadow Freddy?

Nightmare (also known as Nightmare Shadow Freddy or Nightmare Shadow Fredbear) is a black animatronic in Five Nights at Freddy's 4. He is a nightmarish incarnation of Shadow Freddy. ... He is the final antagonist of FNaF 4.

Is shadow Freddy Golden Freddy?

Shadow Freddy has exactly the same appearance as Golden Freddy's "withered" appearance from Five Nights at Freddy's 2, albeit being recolored dark purple. Unlike Golden Freddy, he has large glowing bright eyes and teeth. In Five Nights at Freddy's 3, Shadow Freddy lacks the glowing white effects for his eyes and teeth.