A distant memory
@ topher4167: You get Fake the Sudowoodo.
Fake thinks it is a tree, when in reality, it is not. Likewise, Fake thinks it is not a Rock-Type, when in reality, it is. Fake can never learn (new), nor use Rock-Type moves in battle, since it does not want to let go of its disguise. Furthermore, it must have the Sturdy Ability, & it must learn Wood Hammer as soon as possible (Get a Heart Scale before Blackthorn). Have it solo one Gym Leader of your choice.