Ability₁₃₃-Magician

When a Pokémon with Magician hits another Pokémon with a damaging move, it will steal the held item of the Pokémon that it hit.
⚠️Magician will not activate if the user already has a held item.
⚠️Fling, Natural Gift, Future Sight and Doom Desire do not activate the Ability; Present will activate the Ability only if it deals damage.
⚠️Thief, Covet, Knock Off, Pluck, Bug Bite, and Incinerate will steal or destroy the target's held item before Magician steals it.
⚠️Sticky Barb transfers with its own effect before Magician can steal it.
⚠️Magician will not activate if the Pokémon is holding a Gem even if the Gem is consumed when using the move, but will activate if the Pokémon's held Power Herb is consumed when using the move.
⚠️If a target's consumable held item is triggered by the move (such as a Focus Sash or Lum Berry), it will be consumed before it can be stolen.
⚠️If a target holds a Focus Band or Rocky Helmet, it can be activated by the move, then be stolen by Magician.
⚠️If the Pokémon with Magician faints when using the move (such as due to the target's Liquid Ooze or held Rocky Helmet, or due to the Pokémon with this Ability using a recoil move or a move that causes it to faint), Magician will not steal the item.
⚠️If the move of the Pokémon with Magician triggers Mummy, so that it no longer has the Ability Magician, it cannot steal an item.
⚠️Magician activates after the last strike of a multi-strike move.
⚠️Magician activates even if the user is switched out by U-turn or Volt Switch or the target is switched out by Dragon Tail or Circle Throw.
⚠️Pickpocket activates after Magician, so the Pokémon that has Pickpocket will always end up with the item if the move is a contact move.
⚠️If Meloetta has the Ability Magician (due to Skill Swap etc.) and uses Relic Song, Magician activates before it changes form.
⚠️It cannot steal from a Pokémon with Sticky Hold, unless the move causes the Pokémon with Sticky Hold to faint.
⚠️It cannot steal Mail or a Z-Crystal.
❌It cannot steal a Griseous Orb if either Pokémon is Giratina,
❌a Plate if either Pokémon is Arceus, a memory if either Pokémon is Silvally,
❌a Drive if either Pokémon is Genesect,
❌a Mega Stone if either Pokémon can Mega Evolve using it,
❌a Blue Orb if either Pokémon is Kyogre,
❌a Red Orb if either Pokémon is Groudon,
❌the Rusted Sword if either Pokémon is Zacian,
❌the Rusted Shield if either Pokémon is Zamazenta,
❌or Booster Energy if either Pokémon has the Ability Protosynthesis or Quark Drive.
⚠️Magician has no effect in Tera Raid Battles.
~Bulbapedia