Asked in Pokemon Diamond Pearl and Platinum
How do you obtain Spiritomb in Pokemon platinum?
The same way as in Diamond and Pearl: you need an Odd Keystone. One can found in Twinleaf Town using the Dowsing Machine, they can be dug up in the Underground, though very rarely, and a Black Belt west of Hearthome City will give you one. Then you need to travel to Route 209 and put the Odd Keystone in the Hallowed Tower. Talk to 32 players in the Underground and inspect the Hallowed Tower to have a battle with the Spiritomb. It is possible to get the Spiritomb by following all the steps and then talking to the same player 32 times. To do that you either have to exit the Underground each time you talk to the person and then go back, counting the conversations as separate because one party left, or you can enter your Secret Base and close the door for decorating, then exit the Base and talk to the same person again, which counts because Wireless Communications would have been disabled whilst you were in the Base with the door shut.