How do you get to the peak of Mt. Cornet?

I reckon you have 7 badges and released the three Pokemon from the Galactic HQ? Once you have that done, start at either Oreburgh City or Hearthome City, it doesn't matter. From Hearthome, it's a shorter distance to Mt. Coronet, but from Oreburgh, your destination is shorter once you're in Mt. Coronet.

ANYWAY! You should have surf, strength [optional], and rock climb. I would reccomend having all these HM's on your Pokemon, along with a few full restores and revives, just in case. Also, buy a bunch of ultra balls and dusk balls, because when you do reach the top, you'll battle a level 47 Dialga.

Wherever you start at in Mt. Coronet, you should be starting at the entrance/exit that leads to Oreburgh. Go up and use surf to the right, and use rock climb up the rocks. In the back of the room you end up in, there should be an opening. However, you'll be out of luck if you haven't been to the 3 lakes and then ventured through the Galactic Warehouse and HQ in Veilstone, and released the 3 Pokemon, because instead of an opening, there would have been a depiction similar to that of in the cave in Celestic in that same place. Moving on, go in the opening, and go up the stairs. Battle the 2 grunts and go out of the cave.

From here, venture along the side of Mt. Coronet by going east and then north, and using rock climb on the wall. Go west and go in the cave you come across.

Use rock climb in that cave and go east and exit that cave. Once outside, go down the stairs and use rock climb on the wall to your left. Then keep going left, using strength as a shortcut to avoid the grass, and go in the cave at the end to the north. From here, it's VERY straightforward, and you just need to follow the path and you'll be out of the cave, and you'll be in "Spear Pillar".

Remember, HAVE SOME ULTRA BALLS AND DUSK BALLS [dusk balls, because I reccomend battling/catching Dialga at night]. I'd save the master ball for Cresselia once you obtain the national dex. Trust me on this...

And that's all there is to it. Basically, once you're in the cave, go as north as you can and you'll reach the top. That's how I did it, at least.

hey v-gamer i got a question for u. What if there is a guy blocking your way up to the piller. he says like"im loley lost, pease ijnoe the grunt with no pokemon" Who i get him to move cause i have 7 badges and i released the 3 pokemon.

I recommend starting at Oreburgh City.

To start, get someone with Surf, and someone with Rock Climb. Strength would also be a big asset.

Go up that little mud slide. Enter Mt.Coronet from there.

From there, you should see a top area, where you can surf. Surf across there and you should be able to go up the Rock Slide. (Use Rock Climb.)

Next area. You should be able to go up, and there is the peak. You need to Rock Climb at an area and there's a hidden cave... Go in there, and you need to follow the way and then the exit to that part will arise. It's really simple after that. The reason you MIGHT want Strength is so that if you want to avoid Wild Battles, you can use Strength to go around avoiding the battles.

To be honest, big finger74, I have no idea. Or at least I don't remember.

But I don't think I've ever encountered him? Where is he in Mt. Coronet? Are you sure you're going the right way, and in the right caves?