PIKACHU.
There is none.
Edit: Best stated is Arcanine, I maybe be wrong please correct me if this is so.
There are 18 Fire Attacks in Pokemon Diamond, Pearl and Platinum.
Its best if you have 1 fire Pokemon and 1 ground Pokemon.
I think Infernape,Rapidash, Flareon and Magmortar.
Omg ok this is how you get blastoise for platinum first you ust migrate from fire red........... You could buy fire red in best buy or ebay.....
the best fire Pokemon u could have to beat the elite 4 would be blaziken over level 75 or higher
use a fire Pokemon
With something called CHEATS.
migrate it from Pokemon fire red version
fire-type pokemon.
try your best to find spirtomb in Pokemon platinum
no Pokemon evolves with a fire stone in Pokemon platinum except eevee which turns in to flareon
the best attack for infernape are bulk up, flamethrower ,thunderpunch and brickbreak