You cannot. If you are playing a legit version of diamond of pearl you have to pal park it and get it off someone who has the version with celibi in it. That is the only way.
Alternatively if you own an r4 you can just Google for a program that allows you to spawn Pokemon and abuse them in every way possible.
you cant you have to migrate to get celibe
neither of them is better, they are both the same, but in diamond, you catch dialga, and in pearl, you catch palkia, and you can catch different Pokemon in each game for example: you can catch this Pokemon in diamond, but not pearl but: you can catch this different Pokemon in pearl, but not diamond
You cannot catch palkia in diamond and dialga in pearl but you can catch both of them in Pokemon platinum
In a way. In pearl, you catch palkia. And in diamond, you catch dialga.
You can't catch it on Diamond, but on Pearl you can find it in the Eterna Forest at night.
To catch palkia you will need to trade him with Pokemon pearl. NOTE: You catch palkia in pearl and dialga in diamond.
No
No, you can't catch Deoxys on Pokemon Diamond & Pearl unless you have cheats. You can transfer it from your GBA to Pokemon Diamond and Pearl though
Not much. Pokemon diamond and Pokemon pearl have different Pokemon. for example, in pearl you can catch a glameow but not a cranidos and in diamond you can catch a cranidos but not a gleameow. And at the end of pearl you can catch Palkia the legendary and at the end of Diamond you can catch Diagla. But the games are basically the same. And there you go.....
Event
In Diamond and Pearl you can't catch Articuno.
trade diamond from Pokemon diamond onto Pokemon pearl