Giratina (from Pokemon Diamond and Pearl) isn't in Pokemon Gold, Silver or Crystal. But if you mean Pokemon Platinum (the sequel to Diamond and Pearl), then yes. However Pokemon Platinum hasn't been released yet.
get giratina
You can't genius, its only in Pokemon planinum version because that's when giratina was made.
If you can trade Pokemon from crystal version to gold version my guess is yes
Registeel doesn't exist in crystal version.
At spear pillar, distortion world
Giratina is not found through normal game play. You must have an Arceus from the Arceus event that took place a while ago to get Giratina.
Giratina doesn't "turn" shiny you find a shiny version or get one from an action replay.
To trade Pokemon from Pokemon Crystal version to another version of Crystal you need to use a link cable. You can also battle this way.
Crystal version.
no it cant because it is awesome and is really rare!
In Pokemon Crystal Version, a Heracross will occasionally appear when you use headbutt on trees.
You can't get Giratina in the wild. You can trade for it or transfer it to the Transfer Lab.