Here is what you do -
(Basically Golbat evolves into Crobat due to happiness. If you have owned a Golbat for long for example (You caught it as a Zubat a Level 9) then all you have to do is give it PokeBlocks and in Emerald you can give it special berries that increase it's happiness.
If that doesn't work you can try these which are proven to work.
1. Put the Pokemon in the front of your party (Make it your active Pokemon)
2.Give it heal items when it is unwell and other items such as Carbos and Iron
3.Use berries that promote friendship, such as Pomeg, Kelpsy, Qualot, Hondew, Greppa or Tamato Berries (YOU CAN ALSO USE HIGH LEVEL POKEBLOCKS)
4.Take the Pokemon for massages in Veilstone or in the Resort Area's Ribbon Syndicate
5.Level up the Pokemon and involve it in lots of battles and contests
6.Try not to let the Pokemon faint or lose
7.Let it hold an item - any item, but to promote friendship use a Soothe Bell
These methods are sure to increase your Pokemon's friendship/happiness with you. Use the Poke App 'Friendship Checker' to check how the Pokemon feels towards you.
I got mine as a Zubat @ level 9 and in the Oreburgh Mines, and i have been continuously using it. it was tough but i raised it to level 22 so it could evolve to Golbat. Then i just kept using it in battle and it evolved into Crobat for me @ level 32.
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If you're using Pokemon SoulSilver/HeartGold, the only way you can check your pokemon's happiness is via the girl who is north of the bike shop, who will give you a general estimate of your Pokemon's happiness.
Crobat does not evolve.
Crobat does not evolve: it is the second evolution of Zubat through Golbat.
The Weakness Of Crobat's Are Rock, Psychic, Electric and Ice.
Crobat learns air slash at level 51
yes it is the 2nd best move for crobat
Crobat is the evolved form of Golbat to evolve it to Crobat it needs max friendship with its trainer.
Crobat doesn't evolve.
Crobat can be found in any cave
You can't find crobat you just evolve golbat.
Crobat does not evolve into anything.
Crobat does not evolve.
Crobat doesn't evolve.
Crobat is not usually found in the wild. You have to evolve a Golbat.
Crobat evolves when leveled up with high friendship
Crobat doesn't evolve sorry!!
Crobat does not evolve: it is the second evolution of Zubat through Golbat.
The Weakness Of Crobat's Are Rock, Psychic, Electric and Ice.