I think you must be confused because Sinnoh is the region of Pokemon diamond and pearl not a thing.
Yeah, I think you must be confused too, Sinnoh is the region of Diamond/Pearl/Platinum. Get any of those three games if you want to explore the Sinnoh Region.
sinnoh
you cant get to sinnoh in heart gold, but you can find the gym leaders from sinnoh.
First Sinnoh theme: Diamond and Pearl Second Sinnoh theme: DP Galactic Battle Third Sinnoh theme: DP Battle Dimension Last Sinnoh theme: DP Sinnoh League Victors
there is no sinnoh region
you can't get sinnoh in heartgold.
No there is no way to get to Sinnoh.
mossdeep is not in sinnoh
You have to have arceus to get to sinnoh but only once
Registeel is not in the Sinnoh Pokedex. :)
u get 134 Pokemon in sinnoh
Finneon is 134 in Sinnoh Dex
Sinnoh Sound is a Radio Channel that lets you catch different Sinnoh Pokémon depending upon your location.