From Pixelmon Wiki
The Master Ball is a type of Poké Ball that will always catch the Pokémon it is used on (unless the Pokémon cannot be caught, like a boss Pokémon or another trainer's Pokémon). Unlike all other Poké Balls, Master Balls have no chance of breaking if thrown against a block. A Master Ball can be obtained as a tier 3 special drop, or as a possible drop from legendary and ultimate boss Pokémon. Master Balls cannot be crafted.
|Master Ball||Bastion Remnant||Treasure chest||1||1.9%|
The Master Ball was formerly able to be crafted. This recipe has since been removed from Pixelmon.