Pok?mon Emerald differs from Ruby and Sapphire in that you fight both Team Magma and Team Aqua. After defeating Team Magma, the team departs with Team Aqua in pursuit. The next step continues your progress.
Go down Jaggered Path
Walk down Jaggered Path until you run into a suspicious-looking Magma Grunt next to a rock.
Battle the Magma Grunt
After defeating the Magma Grunt in battle, he mentions a hideout.
Obtain the Magma Symbol
Defeat the Team Aqua Grunts, and then talk to the lady. She gives you the Magma Symbol.
Go to the hideout
Return to the spot where the suspicious Magma Grunt told you about the hideout. The Magma Symbol causes an opening to become visible. Enter the hideout.
Defeat enemies, and pick up items
There are many Magma Grunts to defeat and plenty of items to assist you.
As you walk through the hideout, you eventually run into Tabitha. After winning the battle against him, you find Maxie and Groudon sleeping. Maxie uses the Blue Orb to wake Groudon. After waking up, Groudon runs away. Maxie believes you are at fault and challenges you to a battle.
After losing the battle, Maxie flees, and Team Magma has lost.