Beating Elite 4 Pokemon Diamond?

Question

My Pokemon's r: Empoleon Lvl 61:Blizzard, Hydro Pump, Surf and Grass Knot (To kill Quassagire OHKO)(I'll Change it 4 Ice Beam)

Luxray Lvl 55: Thunder, Thunderbolt, Hyper Beam and Crunch

Dialga Lvl 52: Metal Claw, AncientPower, Flamethrower and Roar of Time

Mespirit Lvl 50:Confusion, Lucky Chant, Future Sight and Charm

Riolu (Training With the EXP. Share) 27 (Lvling up): Quick Attack, Feint, Force Palm and Reversal

PLEASE HELP ME!

Answer 1

All I did was get a Raqauza from my GBA game, all you need.