you must trade haunter to evole it
No. the only way to evolve Haunter is to trade it.
If you just trade the haunter with no items it will evolve to gengar now take it back so that you have the gengar. You can't evolve a haunter by migrating it.
Haunter doesn't evolve at any level to evolve your haunter you need to do a link trade with a friend and he he will then evolve
You evolve it into Haunter at Level 25. To evolve Haunter into a Gengar, you need to trade it.
You'll need to trade for a Haunter in order for it to evolve into Gengar.
you must trade your haunter to evolve it into a gengar
OF COURSE!! you'll need to trade an haunter to a friend, and haunter will evolve TO GENGAR
haunter has to be traded to evlove haunter evolve into gengar in level 42
You have to trade haunter to a friend to evolve it.
Haunter will only evolve through trade.
Gastly evolves into Haunter at level 25, then trade it and it will evolve again into Gengar.
you have to evolve him into a haunter first then trade haunter to someone and it will evolve