Maybe
for a medicham (hint: get a very high level medicham because the haunter will be the same level!)
'Cause it was from sinnoh, or it was already traded from diamond or pearl with a cheat.
The pre-evolution of Haunter is Ghastly. To evolve Haunter you must trade it to Friend and have them trade it back.
You can not find an NPC to trade with, no NPC will. You have to have a friend who owns Firered or Leaf Green & trade with a REAL LIFE friend, trade back...then.....WHAT, HAUNTER IS EVOLVING!
Haunter is one of a few Pokemon that needs to be traded to evolve. A list of a few others Graveler, Machoke, Kadabra. Those are just off the top of my head. But you will need to trade it to a friend and have them trade it back.
You trade haunter to get gengar.
you have to have a medicham and trade it with the girl in snowpoint town for a haunter
Haunter will only evolve when you trade it with someone.
Some lady in a city will trade you it but it will stay as haunter.
Actually, Haunter does evolve. Its evolves into Gengar when you trade it.
you get it over a trade.
You trade Haunter to another Diamond, Pearl, or Platinum version and it will evolve into a Gengar. You will need to trade back to your original Diamond game to get the Gengar. Hope I helped, bye
Nothing, to evolve haunter you have to trade him...
Trade a Haunter and it will evolve into gengar
trade
25 into Haunter and then if u trade Haunter he evolves into Gengar
You trade Haunter it it will become a Gengar.