Normally, each time you walk up to the trailer in Pikachu Valley, one or more Pikachus will appear and walk out of it. However, there is a rare chance that a Mimikyu will appear instead, which will then head back inside, leaving the player character confused. After the first time this happens, if you talk to the Trial Guide standing in front of the trailer, a new text prompt will be added telling the guide about the Mimikyu that appeared, but he responds saying he does not believe you and thinks you are "just seeing things".