Ghost Mouse
From MHWiki
"These tormented souls of slain mice seek vengeance upon the hunters who cursed them to the grave."
The Ghost Mouse is a breed of mice only found in the Mousoleum. They are worth at least 3,590 Gold and considered near impossible to catch.
Ghost Mice are invulnerable to the Physical Power Type, so Shadow traps must be used to catch them. They also only respond to Radioactive Blue cheese.