Hall of Origin
To Get to the Hall of Origin (Japenese: はじまりのま Hall of Origin) in most cases is to find the Azure Flute (Japanese: てんかいのふえ - Heaven Flute), but with the release of Pokémon Heart Gold and Pokémon Soul Silver you can get it through a different event.
After you have the Azure Flute in D/P/Pl, go on the right side of Mt. Coronet or Route 208 and head through the entrance way. When your in there, on the right is a place where you can go through with Rock Smash and on the left you can Surf the way there. Once your done using Rock Smash or Surf, you'll find that you need the HM08 Rock Climb (found at Veilstone City) to get up.
There are also some places where you need to use the HM04 Strength, you'll find some entrances further on that are sort of blocked from view by snow. Once you reach a certain Waterfall at the top then you know that Spear Pillar isn't that far.
Once you reach Spear Pillar, you'll notice a Flute type pattern on the ground, if you step on the platform then it will ask you if you want to blow on your Azure Flute, if you say "yes" then a faint song will play, then some stairs appear and your at the Hall of Origin.
Once you reach the top of the stairs in the Hall of Origin, you'll fight a Pokémon called Arceus
 Capturing Arceus
|Refresh||The user rests to cure itself of a poisoning, burn, or paralysis.|
|Future Sight||Two turns after this move is used, the foe is attacked with a hunk of psychic energy.|
|Recover||A self-healing move. The user restores its own HP by up to half of its max HP.|
|Hyper Beam||The foe is attacked with a powerful beam. The user must rest on the next turn to regain its energy.|
A good way to capture Arceus is to put it to sleep or freeze it, that way it can't move or effect you at all. After that get a fighting Pokémon out and make a hard hit to Arceus (Its defence isn't the greatest), it should be enough to throw a Pokéball in.
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