There is no "best" team. Just get many Pokemon with good abilities and attacks and put them in your party, if you train them very well you will have a "best" team.
ash and pole
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The best Pokemon team in diamond is piplup, shinx, starly, machop, budew, and cranidos
mainly its your rival inpokemon platinum but Cynthia on Pokemon diamond and pearl
i say u have a pretty dicent team but it's not the best i have had better.
fire, bug, and poison types of course!
Both Pokemon Diamond and Pearl have Team Galactic as the main antagonist team.
Empoleon, Diagla, spiritomb, staraptor, golem/steelix, rapidash or giratina
You can't join team rocket in Pokemon diamond. Actually team rocket is not on the game
There is no best team. Just have one water and fire and some other types.PS. Make it mixed!
the diamond beauties are a majorette and dance team
I use Ho-oh arceus darkrai jirachi groudon and deoxys