After you have all eight badges, at Route 10 you will be informed about the roaming pokémon Thundurus. You will need Thundurus to make Landorus appear, but you also need Tornadus. Tornadus is also a roaming pokémon, but in Black. So you have to transfer it to White.
If you have both in your team, go to Abundant Shrine off Route 14, and Landorus will be at the north.
they r legendaries
Either with action replay or luck; Shinies appear very rarely among any pokemon, let alone legendaries.
Defeat all the gym leaders and then legendaries will appear on the maps.
you can find legendaries in any map after you've finished all the gyms,dojos and elite four. legendaries will suddenly appear in any map
sinnoh Pokemon won't appear in Sapphire version!
They appear after you captured or defeated Dialga/Palkia depending on your version.
There is no specific code that allows only legendary Pokemon to appear. However, there are Pokemon modifiers. Use these at your own risk.
In Pokemon Crystal Version, a Heracross will occasionally appear when you use headbutt on trees.
A Shiny Pokemon can be found anywhere as long as wild Pokemon appear; even legendaries like Palkia or Dialga can appear Shiny! They are just extremely rare with a very low chance of 1/8192 encounters to find a Shiny.
it makes wild Pokemon less likely to appear
Celebi does not appear in the gold or silver games, however he does appear in Pokemon crystal.
The point of the game is finding them yourself