Reserving for QWAZ.
EDIT: Take Voldemort the Pawniard.
When you catch him, Voldemort has fled his family for reasons unknown to you. Not knowing what to do with him, you trade him to your Pokemon White version. This must be done before Elesa. He sees Elesa and rages, because he didn't quite know what to do against Electric-types. Therefore, he must solo Elesa. Congrats, you now have a murderer on your hands. Attempt to solo Clay. If you fail, you must release one of your Pokemon. (Does not have to be a Scramblemon.) Then, have him solo 25 of that Pokemon you just released. If you solo Clay, you have no more restrictions for the rest of the run.
Voldemort believes that he is the ultimate spellcaster, and so you must have Hidden Power on his movepool. You must only have one Physical attack. It wants to be the best Special Attacker, so solo 20 Litwick, with Hidden Power unless your type is Fighting. Then, if you did not solo Clay earlier, you must now complete the Gauntlet, to void all your restrictions and allow you to evolve.
THE GAUNTLET:
-Glacier slow: Solo all trainers in Brycen's Gym, excluding Brycen. Do not OHKO any of those Pokemon.
-Hax kid: Solo 10 Axew.
-Inner Kung Fu: Solo 15 Fighting-types with Hidden Power.
-Friends or Enemies: Solo 15 wild Pawniard.
-Dragon Master: Solo Iris.
No matter what you do, you cannot void the next restriction, which is to solo Ghestis's impostor Bisharp.
Good luck!