There are 8 (non-event) Pokemon in Pokemon Pearl.
Palkia
The top of Mt. Coronet, Spear Pillar, contains the first of the legendary Pokemon; Palkia. You battle it right after fighting a lot of Team Galactic, so you'll be severely weakened. To make up for this, it's catch rate is 30%, unlike the rest, which are 3%.
Mesprit, Uxie, and Azelf
The next legendary Pokemon you can obtain are Mesprit, Uxie, and Azelf. They are all at level 50. You battle Uxie and Azelf in their respective caverns, but when you try to battle Mesprit, it runs away and roams the grasses of Sinnoh. You can find it by using the marking map app on your Poketch.
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After the National Dex
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Heatran
After you obtain the National Dex, you can catch Heatran deep in a volcano. First, go to Stark Mountain, near the survival area. You will meet up with someone to get you through, and when you arrive at the end, whe will take the stone and leave. Go back to her house in the Survival area and talk to her; she will leave. Now go back to Stark Mountain, and head to the place where you found the stone. Heatran will be there at level 70.
Regigigas
To catch Regigigas, you need to have transferredRegirock, Regice, and Registeel over to Pearl from one of the third generation games. Put them in your party, and go to Snowpoint City. There is a Temple there. Go all the way down the stairs, and you will find a statue. Talk to it, and Regigigas will awaken at level 70.
Giratina
The Penultimate Pokemon is the third dragon in the Palkia and Dialga triangle. If you look at your map, it will show a new lake, not far from Veilstone City. Go there, and you will enter Turnback Cave. The rooms are generated at random, so you can go any direction except the way you came. Eventually, after passing three pillars, you will see Giratina hovering. He is at level 70.
Cresselia
The final Pokemon is the Lunar Pokemon: Cresselia. Go to Canalave city, and go to Sailor Eldritch's House. Inside you will find a boy having a nightmare. Talk to his mother, and then to the sailor. He will take you to Full Moon Island. Once there, follow the short path to where Cresselia waits. Like Mesprit, it will fly off, but you can again use the Marking Map. It is level 50.
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Many fans Debate as to whether Rotom should be counted as legendary. I think He should be, therefore I will count him as the ninth.
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Rotom
Rotom is more hidden than the rest of the Legendary Pokemon. Go back to Eterna Forest During the Night. Near the end, you will find a tree that you can cut down. Keep going, and you will find a mansion. In the mansion, there are many ghost Pokemon, as well as some ghosts of people. Go up the staircase, and through the door at the north. Once in the hall, go one door left, and you should see a TV set. Walk over and Interact with it. Rotom will appear at level 15.
The legendary is palkia
It's not a legendary in Pokémon Pearl.
on Pokemon pearl you only see 1
the legendary Pokemon in diamond and pearl are dialga and palkia.
No, but there is a Rotom in the TV.
Palkia
The dragon pokemon palkia.
you find the legendary Pokemon heatran
Empoleon is not a legendary Pokemon. It is the final evolution of Piplup, one of the starter Pokemon in Pokemon Diamond, Pearl, and Platinum.
Stark Mountain
No, because it is a legendary.
On Pokemon pearl there are multiple legendary Pokemon. The first true legendary is probbaly palkia. Rotom and spiritomb etc are just sub legendarys. You can also get heatran giratina shaymin and arceus in Pokemon pearl. references,ive finished the game 10 times aswell as platinum and diamond.