Pokemon
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Universal Information
¤ What is this section?
¤ Breeding Pokemon
¤ Elemental Types
¤ Pokerus Infection
¤ Shiny Pokemon

Affiliates
¤ Amity Square
¤ Dark Eon Hideout
¤ Eevee's Headquarters
¤ Jenviousity
¤ Lugia's Island
¤ Perfect Absolution
¤ Pokemon Inferno
¤ Pokeshore
¤ PokeTech
¤ Pokeuniverse
¤ Pokemon Valley
¤ Sapphire Milotic
¤ The Spriting Shack

A Pokemon you would not normally see until you battle Cynthia is Spiritomb, a Ghost/Dark-type Pokemon. It can't be found via the Pokedex, so how does one find it?

In order to find it, you'll need an item called "Odd Keystone." You get this item from a man on Route 208 or in the Sinnoh Underground. Once you have this item, go to Route 209 and look for an oddly shapped structure that looks like a lot of rocks. Insert the keystone item in here, and you'll complete some sort of tower.

Once you do this, get with some friends and go to the Sinnoh Underground. Talk to all your friends, leave the underground, and return. Talk to them again. Keep doing this until your Underground card says you have talked to 32 people.

Return to the Tower and look down it, you'll be attacked by a wild Spiritomb. Its at a low level, so you'll want to bring some equal level Pokemon and weaken it before attempting to capture it.