Power Lens
From Pixelmon Wiki
A Power Lens is a type of power item that can be given to a Pokémon. When a Pokémon holding a Power Lens defeats an opponent Pokémon, it will earn the normal EV gains from the opponent along with 8 extra Special Attack EVs. However, the Pokémon's Speed will be halved while wearing a Power Lens. When a breeding Pokémon holds a Power Lens, its Special Attack IV is guaranteed to be passed to its offspring.
The power lens can be obtained as a drop from rare tier bosses, found in pillager outpost chests, or as a tier 3 or 4 special drop.