Bad Time Mode is an Easter Egg Mode in Yandere Simulator.


This mode is a reference to the video game Undertale. Press U to activate the mode. It cannot be deactivated until the game is reset or the day ends. Yandere-chan will resemble the character Sans from said game. She will have light grey skin with black eye sockets. She will be bald, and when any special attacks are used, her left eye will glow blue. The player will not wear the school uniform, but a blue jacket and black pants with white stripes. When idle, she will place her hands in her sweatshirt pocket and sway side to side.

Until the February 15th, 2016 Build, the song "Megalovania" from Undertale would play the entire time. This was replaced with the theme of Monty on the Run. In the June 15th, 2016 Build, this mode was finally given an original song in order to avoid copyright infringement. In the July 8th, 2016 Build, the song was replaced by a new original song.


During this mode, the player can use several attacks that Sans uses during the Genocide Route to kill students, teachers, and Senpai.

Dragon Skulls

If the player presses the Left Control on their keyboard, a large, six eyed skull appear and shoot a white ray that will kill anything in its way. Pressing Left Control a second time will make two blasters appear, pressing it a third time will make three appear, and so on until the fifth blaster, which will reset the amount to one. The player can use the Skulls to kill Senpai.

They were originally modeled after Gaster Blasters, but were changed by the request of Toby Fox.


It is impossible to interact with any student in this mode as the button for Psychokinesis replaces the talk or attack button. Once close enough to a student or teacher, the player can pick up them and throw them around. Students who witness the floating corpse will treat it as a random corpse, so no Heroic or Strict teachers will come to attack the player. This attack is unavailable to use on Senpai, as he is completely uninteractable due to his aura.

Once the player lets go of a character's corpse after killing them with psychokinesis, they will not be able to pick them up with the attack again.

Bone Attack

If the player holds down Left Control, many bones will rise from the ground within a short range. Any student or teacher that comes within contact with a bone will die instantly. The bones will appear through any prop, including walls. This bone attack can be used to kill Senpai.


  • Yandere-chan's textures will glitch if she wears gloves. If the player takes off the gloves, then Yandere-chan will have the normal school uniform.
  • Yandere-chan will lose her skin texture if she goes nude in the Shower Room. If she puts on a uniform, she will revert back to Yandere-chan, but with her powers still activated.
  • If Yandere-chan uses the bone attack while Kokona is eating on Wednesday, she will die. If the player picks up her body, she will continue her eating animation while Yandere-chan is carrying her.
  • If the player uses psychokinesis in front of the delinquents, they will run up and hit her with their weapons, but she will not fall into a coma. Once she drops the student, the delinquent will continue to follow her around without harming Yandere-chan.
  • If Senpai is killed in this mode and dismembered, Yandere-chan can carry one of his body parts and walk out of the school into a small part of the town.


  • This mode was implemented in the January 15th, 2016 Build.
  • Press D to disable the copyrighted music.
  • If Senpai is killed with this mode, he will simply respawn the following day.
  • Yandere-chan's eyes change to a single blue glowing eye when she uses her attacks.
  • When not moving, Yandere-chan will sway her hips similar to the way she does in Ebola Mode.
  • Osana Najimi will use the same hip sway animation that Yandere-chan uses in this mode.