I'll reserve for Level 51 then.
EDIT: Take Fragile the Roggenrola.
Fragile has Sturdy, but does not think that it does. Therefore, every time it is saved by Sturdy, you must buy a Revive and immediately trash it. If you do not have access to Revives yet, keep track of your "debt" and pay it off ASAP. Now, it does not believe in type advantages, so it may not battle any trainer Pokemon whose STAB it resists or is weak to its own STAB. Since most people tend to use Roggenrola in Nuzlockes because Lenora is so F***ing hard, he may not fight Lenora. In fact, he may not fight any Gym Leaders. It also thinks that you are playing a Scramblocke, so you get 5 lives. Every time it faints, it loses a life. If it loses all 5 lives, you must release him, catch another Roggenrola at the same level you caught him, name it Fragile, and you start with 4 lives. Then 3. Then 2. Then 1. All other resurrections will have one life. Roggenrola may only evolve into Boldore before Burgh if and only if he has not lost a single life. It may not evolve into Gigalith. Solo N.
As always, I have to say GLHF, but now I don't really mean it.