you have to beat the elite four 5 times in both reigons
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No, it's only on FR/LG/E.
You cannot find Deoxys in Pokemon HeartGold. Deoxys has to be traded from another game to get into HeartGold. The rocks to the east of Pewter City are used to change Deoxys' forms, but you have to transfer one using Pal Park, first.
You cannot find Deoxys in HeartGold, or SoulSilver. You can only get Deoxys through trading or at a Pokemon Event.
Unfortunatly, not -.-
You can't
It is impossible to catch a Deoxys in the wild in HeartGold & SoulSilver. You need to get one at a Nintendo Event or transfer one from a GBA game. Theres a Deoxys mission in the 3rd Ranger game. Capture it and it will be comfortable in any 4th gen game.
No, it's only on E/FR/LG.
If you have action replay you can get any Pokemon you want. This feature works only in Pokemon Heartgold , Soulsilver and Platinum.
You cannot find a wild Deoxys in in Pokemon Soul Silver, or HeartGold. Deoxys can only be obtained by trading with someone or by getting one at special distributions.
Go to Pewter City and there are meteorites there. Check it and I think Deoxys will change form. (There are 4 rocks: for each of the 4 forms.)
Deoxys didn't exist when Pokemon Gold, Silver, and Crystal came out. If you meant HeartGold, then you'll need to migrate it or trade for it.
There is no such thing as a tree that leads to a man who gives you a Deoxys. You cannot get a Deoxys through normal game play in HeartGold. You must trade a Deoxys from another game.
There are meteors in between pewter city and mt.moon that can change deoxys form