i do not know what "string" against,but i think you mean strong against.
haunter is a ghost and poison,so its strong against grass,ghost,and psychic pokemon.thats the ghost & poison good-against.haunter can learn a lot of moves,so learn your ypes chart!
by:poke-expert rookie pearl
Yes, Haunter is a very good Pokemon
Haunter is a ghost type Pokemon
look in the Pokemon tower in lavender for haunter. note, haunter is hard to find in the Pokemon tower
You trade haunter to get gengar.
Haunter evolves when traded
Trade Haunter and you will get a Gengar.
You can get a Haunter in Almia Castle.
you can't find haunter in Black
You will need to level up Haunter to level 50 to evolve it in Pokemon Resolute.
Haunter can only be evolved into Gengar via Trading (such is the case in all Pokemon titles that include Haunter, not just Silver).
Some lady in a city will trade you it but it will stay as haunter.
Haunter evolves through a trade.