all moves are able to use against that
^yess all moves can be used, but bug moves would be best because
confusion is a psychic move.(:
Dark and Ghost-type moves are the most effective moves to use against Psychic-type Pokemon.
Fighting and Ground type moves are most effective against dialga, since it is a dragon+steel type pokemon.
earthquake
some Physic type moves Confusion, Physic, etc..
sometimes.
Cynthia's Pokemon and their weaknesses: Milotic is weak against electric Lucario is weak against fire type moves and earthquake Garchomp is weak against dragon-type moves Spiritomb is weak against water Sorry, I forgot the rest. I hope this helps a lot!
Use Fightning moves.
use ground moves against him. i suggest use earthquake if one of ur Pokemon knows it or even use gastrodon against him using muddy water.
I think arceus is the the strongest Pokemon in diamond and pearl. Also no moves are supereffective on Spiritomb and arceus
Dragon type moves are only super effective against Dragon type Pokemon.
in gun city
Go to seribi.net and they have everything there