Pokemon SCARLET NUZLOCKE With Only MEGAS

Trying again. Playing Pokemon Scarlet, except I can only use Pokemon capable of mega evolving, and their pre-evolutions.
1. If a Pokemon faints, it's dead
2. I can only catch Pokemon capable of mega evolving, or who can evolve into Pokemon capable of mega evolving
3. I can only catch one Pokemon for every badge
4. I can catch shiny Pokemon, but I can't use them unless they meet the other criteria