It is inposible to tel the exact way...But you haf to beat the 7 gym leader and then go back to Heartrome city go to the cave to the left of Heartrome. Then you youse surf at the top water then youse rock climb then you go up stairs. ps. you DON'T need a master ball.
You have to go east of eterna city.
right at the top on spear pillar :)
at the end of the cave
you catch dialga in the spear pillar and get to snowpoint city
All you have to do is you do 7 gyms then come back and he/she has gone
He only does in diamond, not pearl. Once you beat galactic boss Cyrus on spear pillar you will battle dialga with the music dialga and palkia battle at spear pillar!
It is at the top of mt.coronet
In Pokemon Platinum, the player can find Cyrus at the top of the Spear Pillar through Mount Coronet. The player needs Pokemon who know Surf and Rock Climb to reach the top of the pillar. They must also have freed all three emotion Pokemon and gained the seventh badge.
In Pokemon Diamond and Pearl only, it is on the top floor of the Lost Tower.
on top of mt cornet
in the top of mt cornet
It is on top of Mt.Coronet