smeargle
You can get Duskull by using the Pokeradar on Route 224 in Pokemon Diamond. You must use the Pokeradar at night in order to find and catch Duskull.
the Pokemon that dawns little sister tells you
You can get a Larvitar on Pokemon Diamond by using the Pokeradar on Route 207. If you're using Pokemon Pearl, you'll need to trade with Diamond.
pokeradar is only at Pokemon pearl , diamond and platinum.
the Pokemon you would normally find but with pokeradar you can get the shiny version of that Pokemon but that takes hours and there are some special rules for to get it. also pokeapp 20 is something you can use with using the pokeradar
218 with pokeradar
Trapinch can be found on route 228 on both Diamond and Pearl using the PokeRadar.
By pal park, by pokeradar.
You get it after you beat the pokedex.
pokeradar on route 222
You can only get Wynaut in-game by breeding Wobbuffet, which you can get at the three lakes by using the PokeRadar.
The Pokeradar is not an option in Pokemon SoulSilver. The Pokeradar is only available on the Pokewalker accessory that came with your copy of Pokemon SoulSilver. Plus, the Pokeradar was introduced in Pokemon Diamond, Pearl, and Platinum, not in Gold, Silver, or Crystal.