Girratina, Dialge, Palkia, are all good legendaries. If you are asking for non-legendaries, gliscor, starters, evoulutions of eevee, and abamasnow are good. If anyone else have suggestions, please add.
No, Bibarel's are one of the worst wild pokemon there are in pokemon platinum pearl or diamond
by battling with strong Pokemon
Just get STRONG Pokemon
No.
when i play Pokemon platinum theres no one that want to trade Shieldon for strong Pokemon i hope you understand it
You use your strong(est) Pokemon to kill the Gym Leader's Pokemon.
no way i ain't givin you my shaymin or darkrai
Any Pokemon strong to water: Electric types and grass types work the best.
Infernape, or other fire pokemon.
train your Pokemon alot. i got all of my Pokemon to level 18 before the first gym because i trained them alot.
There is no rental Pokemon in in Pokemon platinum
you haft to have strong Pokemon and no Cynthia dosent have a legandery because ive beaten hewr before