Pokemon Diamond Walkthrough: Snowpoint City to Mt. Coronet
Part 8 of our Pokemon Diamond walkthrough takes a break from the quest for gym badges and instead focuses on two massive sidequests. You'll need to take down Team Galactic once and for all as well as face the rare legendary Pokemon Dialga or Palkia.
Back to Veilstone City
After you leave the Snowpoint Gym, be sure to hit up the local Pokemon Center to heal and stock up on healing items at the local Poke Mart. You'll need them for the upcoming battles against Team Galactic and the legendary Pokemon Dialga or Palkia. Just outside Snowpoint City, you'll run into Rival and one of Team Galactic's top commanders. Before you can confront him in battle, though, he'll flee the area. Rival mentions the Team Galactic headquarters, which you may recall seeing--but not being able to access--way back in Veilstone City. That's your next destination, so fly there to bring the fight to Team Galactic.
A lone Team Galactic grunt stands guard at the building's entrance, and he'll run off without a fight, leaving a key behind. This key doesn't let you into the main building, but rather the tiny, green-roofed warehouse off to the left. The key opens the door inside the warehouse's foyer, which leads to a staircase and a secret entrance to the Team Galactic Headquarters.
Team Galactic Headquarters
Head east through the subterranean walkway until you hit another staircase. You'll do battle with a pair of Team Galactic grunts and one of their scientists along the way. Go up two flights of steps to enter the headquarters proper. You'll notice green warp tiles in this room. Step on the tile to the left and then step onto the only other tile in the new room to find a staircase. Continue left through two rooms to find another key, the Galactic Key, and battle a trio of Team Galactic grunts.
Backtrack to the warehouse and back out into Veilstone City. You can now use the Galactic key to open the headquarters' front door. Feel free to use the Pokemon Center or Poke Mart along the way if your Pokemon are worn down from the earlier battles.
The path through the headquarters is straightforward so you won't have to worry about getting lost, but you will get into your fair share of Pokemon battles. You'll fight ten Team Galactic grunts in all, with Pokemon ranging from level 34 to 36 before reaching the final room.
Team Galactic Bosses
At the end of the headquarters you'll come to a locked door. Use the Galactic key on it and you'll enter for fight Team Galactic's head honcho, Team Galactic Boss Cyrus. You may recognize this character from the first time you passed through Mt. Coronet. He reveals that Team Galactic has managed to capture Azelf, Uxie, and Mesprit, so now it's up to you to save them.
First you'll need to take out his high level Pokemon, which include a level 40 Murkrow and Golbat, as well as a level 43 Sneazel. All three should be susceptible to electric-type attacks. Avoid the use of psychic or ghost Pokemon since they're weak against his dark-type Pokemon. Once he's defeated, he'll admit his defeat and hand over the Master Ball and direct you to the warp panel on the other side of the room before fleeing to Mt. Coronet. You'll need to give chase, but first take the warp panel to free the three legendary Pokemon.
In the next, lab-like room you'll face a battle against Team Galactic Commander Saturn. This easier fight pits you against a level 38 Kadabra and Bronzor, as well as a level 40 Toxicroak. Once you've defeated Commander Saturn, he too will flee and Azelf, Mesprit, and Uxie will be saved.
Back to Mt. Coronet
Once again it's time to fly back to the entrance of Mt. Coronet, where you'll have one last battle with Team Galactic and a chance to capture Dialga or Palkia. This time you're going to access the mountain from Route 207 by surfing along the body of water to the east and using a Pokemon with Rock Climb to access the top entrance. Inside you'll need to go down a long series of rocky pathways, battling seven Team Galactic grunts along the way. Their Pokemon are slightly stronger than the grunts at headquarters, ranging from level 37 to 40.
At the end of the path you'll reach Spear Pillar, the site of your final showdown against Team Galactic. Rival will show up to assist you in a pair of double battles. First you'll battle against two ordinary Team Galactic grunts. After that, Commanders Mars and Jupiter will return to exact their revenge for their embarrassment at Lakes Valor and Verity. Fortunately your Rival is a formidable ally and these fights shouldn't be a problem.
Spear Pillar: Final Showdown With Cyrus and the Legendary Pokemon
With Mars and Jupiter out of the way, you're free to take on Cyrus. He's already summoned the legendary Pokemon Dialga (or Palkia if you're playing Pokemon Pearl), but Mesprit arrives to save the day. The legendary Pokemon destroys his Red Chain, the item used to summon Pokemon from another dimension, and shuts the interdimensional portal. With his plans spoiled, Cyrus is quite angry and you're the only outlet for his rage. Prepare for a tough fight against his notably higher level Pokemon. He has a level 45 Honchkrown, Gyrados, and Crobat, as well as a level 48 Weavile. Take them down to vanquish Team Galactic for good.
Team Galactic leaves the scene, but Dialga (or Palkia) remains. You can try to catch the legendary Pokemon the old fashioned way, by weakening it in battle and throwing Ultra Balls. It's much easier to simply use your Master Ball, though, since it's a guaranteed capture. You also won't need the Master Ball later in the game since the other legendary Pokemon are easy to capture.
With Dialga secured, you're ready to take on the final gym leader and then the Elite Four in the final parts of our guide.