This item helps you capture Spiritomb at Route 209. Talk to 32 people underground and then insert this into the Hallowed Tower. This doesn't apply to the Hikers that trade Orbs for Treasures that can be transferred to their corresponding section in the Trainers' Pack.
To obtain it, talk to the guy in the Karate outfit at Route 208 in the right hand corner, or mine underground until you find one.
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