I will be doing a challenge run, and the options will be the mystery challenge and randomised.
I can use a towns PokéCenter up to three times. After that, I can only use items to heal
I cannot use items in battle unless they are Pokéballs of some sort
The game difficulty will be set to hard
I can use the secret base nurse twice every 5 battles or thrice every plot battle. (level trainer doesn’t count)
Further note: Fainting and ending up in a locked center is not breaking the rules, so fainting to heal up fair game. Cyan Cave and Midna Garden nurses also can only be used once.
In case you don’t know the rules of the randomiser or mystery challenge
Randomisers will randomise everything, from wild Pokémon to trainer Pokémon to items in the overworld. The wild Pokémon will also gain items
The mystery challenge gives you the inability to identify a Pokémon until it is registered to the Pokédex