Factors to Consider:
* Rarity: Is the Pokémon extremely rare and difficult to catch normally? (e.g., Shiny Pokémon, Legendaries)
* Importance to your team: Is this Pokémon crucial to your strategy or a vital member of your team?
* Personal attachment: Do you have a special connection to this Pokémon? Maybe it was your first ever catch or you love its design.
* Future use: Do you plan to use this Pokémon in competitive battles or breeding?
Potential Candidates:
* Legendary Pokémon: Many legendaries are incredibly rare and difficult to catch, making a Master Ball a worthwhile investment.
* Shiny Pokémon: Shiny Pokémon are highly sought after for their unique appearance and rarity.
* Starter Pokémon: If you really love your starter Pokémon, you might want to guarantee you catch it.
* Pokémon with specific abilities or moves: Some Pokémon are only obtainable with specific abilities or moves.
* Pokémon you struggle to catch: If you have trouble catching a specific Pokémon, a Master Ball can save you a lot of frustration.
Ultimately, the best Pokémon to use a Master Ball on is the one that brings you the most joy and satisfaction. Don't be afraid to use it on a Pokémon you really want, even if it isn't considered "the best" by others.
Important Note: It's generally recommended to save Master Balls for truly exceptional Pokémon, as they are incredibly rare and valuable.