Q&A for How to Get Crobat in Pokémon Ruby and Sapphire

The only way to get a Crobat is to increase its friendship level to a minimum of 220 score . To level up fast try to increase its friendship by keeping it in your party and by increasing it's happiness by giving some berries.

You can't see it. Just level it up and it'll happen eventually. It won't take forever, but it does take a while.

You have to link trade your Graveler to a friend - it doesn't matter if they have Ruby or Sapphire. Once the Graveler evolves into a Golem, ask your friend to trade it back to you.

Zubat evolves at level 22, then evolves when leveled up with high friendship again.