How do you get Surf in omega ruby?

Question

I really need to get it to cross a river.

Answer 1

You need to beat the fifth Gym leader, which is Norman by going to Petalburg City. Once you defeat Roman, you will get the Retaliate TM and the Balance Badge which allows you to use Surf outside of battle. Then, exit the Gym and go left. In the house to the left of the Gym, you’ll find Wally’s father, who will then give you Surf.

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