In red, blue and yellow. Search around in the Pokemon tower for a while even though you come across countless gastlys. In heartgold and soulsilver, look in either the sprout tower at night or the bell tower (i think also at night) for a gastly to evolve into a haunter. Haunters themselves can be found at night in the safari zone or route 8, according to bulbapedia but i have never found one myself.
Nevermind... You Just Link Trade....^^"
trade it
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
Haunter is a ghost type Pokemon
The pre-evolution of Haunter is Ghastly. To evolve Haunter you must trade it to Friend and have them trade it back.
You'll need to trade for a Haunter in order for it to evolve into Gengar.
Gastly evolves into Haunter at level 25, then trade it and it will evolve again into Gengar.
You trade haunter to get gengar.
you must trade haunter to evole it
You must trade haunter with someone
Trade Haunter and you will get a Gengar.
Haunter evolves by trade
Yes. Haunter evolves into Gengar when traded.