|Color (s): Grayscale|
|Starting Location: CAM 7|
|First appearance: Night 3|
"The sights of Hell bring its viewers back in." -SuicideMouse.avi
Mortimer bears a strong resemblance to the Mickey Mouse as first depicted in his early cartoons, as all of his colors are in grayscale and his features match the original cartoon Mickey Mouse. He walks around with his hands tucked behind his back, aside from the of the Meat Freezer.
- The pose Mortimer uses when he enters the Meat Freezer is a reference to the suicidemouse.avi mock-up video, where Suicide Mouse walks with his hands outstretched.
- If the player manages to survive in-game for a long amount of time, the full Suicidemouse.avi song will play, revealing that it will play the same moaning and screaming from the suicidemouse.avi video in-game. This can be seen in this video.
- The television in the Broadcasting Room will remain on until Mortimer leaves the Office in Remastered 1.0.
- Mortimer was very active in Remastered 1.0 because his A.I. was being tested.
- Mortimer's pet was Suicide Mouse