How to Get Sudowoodo in Sapphire

Insert the "Pokemon Emerald" game cartridge into a GameBoy Advance system. Turn on the GameBoy Advance and load your saved Pokemon game.

Travel to the flower shop on Route 104, south of Rustboro City. Speak to the woman inside to receive a Wailmer Pail as a gift.

Travel to the Slateport City pier and board the ship to the Battle Frontier.

Walk to the southeast section of the Battle Frontier and approach the light-green and tan-colored tree that appears different from all the other trees.

Press "Start" to open the in-game menu. Open your "Key Items" bag and select the Wailmer Pail.

Press "A" to use the Wailmer Pail on Sudowoodo. It will challenge you to a battle. Weaken it until its hit points are in the critical red zone. Throw a Poke Ball to capture it.

Insert the "Pokemon Sapphire" game cartridge into another GameBoy Advance system. Turn on the second GameBoy Advance and load your saved Pokemon game.

Connect the GameBoy link cable between the systems.

Enter the nearest Pokemon Center in your current city on "Pokemon Sapphire." Go upstairs and speak to the nurse standing in the middle.

Answer "Yes" to her question and press "A" to save your game. You will enter a room where you are able to select the Pokemon you wish to trade.

Select Sudowoodo on the other GameBoy Advance system. Choose a Pokemon in your current Pokemon party to trade for Sudowoodo.

Press "Yes" on both GameBoy Advance systems to confirm the trade. You will then receive a Sudowoodo in your "Pokemon Sapphire" version.