Pokemon Diamond/Pearl Walkthrough:

• Veilstone City

Rumble in the Headquarters

The Galactic Veilstone Building (the headquarters) is a tall, black building located at the north-east section of Veilstone City. Talk to your old friend (the Galactic Grunt) outside, and he'll inadvertently leave behind a Storage Key. You can also pick up a PP Up on the left side of the building. Go into the warehouse at the north-west section of the city and unlock the door using your Storage Key. Pick up the Dusk Stone and go downstairs, which leads you to the basement of the Galactic Veilstone Building.

Go straight east and you'll battle a Galactic Grunt, the first of many. Keep on going east, making sure to pick up the Zinc in the room you pass by. At the end of the hallway, go up the stairs. This will take you to a room with one Galactic Grunt who won't battle you, but will tell you about the "warp panels". Continue east up the stairs. In this room, you'll battle a Galatic Grunt and notice two warp panels. Take the right warp panel to pick up TM49 - Snatch. Then go back and take the left warp panel, which will take you to a very small room with a single warp panel. Take that and go up the stairs. Battle the Grunt and take the warp panel on the left. Go downstairs, battle the Scientist, and head down the stairs. Continue west down the hall, and pick up TM36 - Sludge Bomb and the Galactic Key. This key will allow you to unlock any locked doors in the headquarters. Go back to the room where you fought the last Grunt and take the stairs up. Go west, battle the Galactic Grunt, and pick up a hidden Elixir on the machine at the corner. Follow the hallway, unlock the door at the end, and pick up TM21 - Frustration. Now, go back up into the city and enter the actual Galactic Veilstone Building at the north-east section.

Once inside, unlock the door and go up the stairs. Pick up a hidden Full Heal on the machine and head east to battle the two Galactic Grunts. Go into the room and pick up a hidden Ultra Ball on the right machine. Take the bottom-right warp panel outside the room for a Max Revive. Go back into that room and take the warp panel inside. Here, you can heal your Pokemon by sleeping in the beds. Continue up the stairs and pick up another hidden Full Heal on the machine. Go to the end of the hallway and you'll see three warp panels. The middle warp panel will lead you to an Elixir and the one on the left will take you to the boss.

Unlock the door and approach the man inside, who is Galactic Boss Cyrus. After defeating him, he'll give you a Master Ball. Cyrus will leave for Mt. Coronet and tells you to the warp panel ahead to save the Legendary Trio. So, go into the next room and take that warp panel. Go east and then enter the room. Inside are the Legendary Trio trapped inside special cages and Commander Saturn. Defeat him in a battle and you'll be able to free the Pokemon by pressing the button on the control panel. After pressing the button, the three Pokemon will float off, and so will Commander Saturn. To quickly exit the building, go back to where you battled Cyrus, and take the green warp panel out.

Now you want to intercept Cyrus at Mt. Coronet; go there going east from Oreburgh City onto Route 207.