Menderbug

"Member of an elusive guild of bugs fixated on the maintenance of Hallownest's many signs and wayposts. The bugs of Hallownest were obsessed with building things. What strange little minds they had."

Menderbug is an enemy in Hollow Knight. He can be found repairing the sign at the bottom of the well in the Forgotten Crossroads.

Behaviour and Tactics Menderbug has a 2% chance to spawn at the entrance of Forgotten Crossroads right below Dirtmouth. To spawn, the following conditions must be met:
 * The sign at the entrance must be destroyed
 * The player must leave and re-enter the room

Upon seeing the Knight, Menderbug flys away and quickly leaves the room.

To kill Menderbug, enter the Forgotten Crossroads from Dirtmouth using Desolate Dive/Descending Dark. This destroys the sign upon landing and, if he has spawned, also kills Menderbug. He can also be spawned by leaving the room to the west or east within the Forgotten Crossroads; however, this method takes significantly more time and makes it easier to fail to kill Menderbug. One of the easiest ways to catch him is in the late game after acquiring Kingsoul and/or Salubra's Blessing to refill SOUL easily.

Menderbug's Diary After killing Menderbug, his house is unlocked. The house can be found in the same village where Sly is first found infected.

Location Menderbug is located beneath the well in the Forgotten Crossroads.

Trivia
 * There is an unused key found in the game files named Mender_Key and in early dev notes, it is implied that Menderbug would drop this key called an "Odd Key" that would probably then allow access into his house.
 * Killing Menderbug is not needed in order to acquire the Hunter's Mark.
 * Menderbug cannot be read by the Dream Nail.
 * Upon death, Menderbug emits an Infection cloud, despite not showing any hostility like infected creatures do.
 * The sign at the entrance of the Forgotten Crossroads remains broken after Menderbug is killed.
 * Menderbug still spawns in the Infected Crossroads.

References

Починжук Insecto_reparador Majsterobak Fixeur