Srs Bisnis, take a male Totodile named Juggernaut. He is known for having the power to build enough momentum to be an unstoppable force, although that certainly doesn't apply to his mental capacity. So, he must acquire 4 moves that cause some sort of negative recoil effect to the user, and one of them must be Superpower. After learning Superpower at level 43 as a Totodile, he will immediately evolve to Croconaw and then to Feraligator at level 44, reaching his full adult size.
After you complete the Elite Four, you can erase one of your recoil moves and replace it with another move, in celebration of him joining the Brotherhood of Mutants. After this, his moveset is locked in permanently.
Also, solo Whitney's Miltank, the ultimate unstoppable force.
EDIT: KS #2 accepted. Will be replaced if there are enough challanges from people who only post one.
Obbmud99 accepted. For once he didn't troll me.
Nauris accepted in the starter slot, since Arceusstar never fixed his challange.