Unlike in Colosseum, XD has an area where you are capable of battling and capturing Wild Pokémon

There are three areas, Oasis, RockGround, Cave, that you can go to each with Wild Pokémon based on the area. They have to be activated by Duking in Pyrite Town first
What you need to do however in order to lure the wild Pokémon out is leave them food similar to how in Ruby, Sapphire & Emerald you leave PokéSnacks. When you're out and about you May get a symbol pop up on the screen similar to the one to the left. This means that a Pokémon has arrived at a PokéSpot. To check which open up your P*DA and have a look (such as in the picture to the right). The Spots glowing are the ones with Pokémon there. If it's glowing rapidly chances are a Munchlax has come and eaten your PokéSnacks. However usually its not so at your first opportunity and as soon as possible, go back to the PokéSpots and find & battle a Wild Pokémon
And thus the Wild Pokémon appear and you get a chance to capture them.

Below are the Pokémon obtainable in PokéSpot:

Picture No. Name Level Caught Location Catch Rate Gender
#027 Sandshrew Lv. 11-19 RockGround Spot Common 50% Male ♂
50% Female ♀
#207 Gligar Lv. 11-19 RockGround Spot Uncommon 50% Male ♂
50% Female ♀
#328 Trapinch Lv. 11-19 RockGround Spot Rare 50% Male ♂
50% Female ♀
#187 Hoppip Lv. 11-19 Oasis Spot Common 50% Male ♂
50% Female ♀
#231 Phanpy Lv. 11-19 Oasis Spot Uncommon 50% Male ♂
50% Female ♀
#283 Surskit Lv. 11-19 Oasis Spot Rare 50% Male ♂
50% Female ♀
#041 Zubat Lv. 11-19 Cave Spot Common 50% Male ♂
50% Female ♀
#304 Aron Lv. 11-19 Cave Spot Uncommon 50% Male ♂
50% Female ♀
#194 Wooper Lv. 11-19 Cave Spot Rare 50% Male ♂
50% Female ♀

 
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