Spell Tagin Pokémon Polished Crystal

Boosts Ghost-type moves by 20%. (Hold) Spell Tag powers up Ghost-type moves by 20%. Ghost has great offensive coverage, only being resisted by Normal (immune) and Dark, so the boost is valuable. This is a solid item for Ghost-types like Gengar or Mismagius who want consistent damage without downsides. Wild Ghost-types sometimes carry these if you're looking to farm one.