Pokemon Platinum

Pokemon Platinum is the fourth generation game of Pokemon series. It still consists of the same mission as the previous series, collect all the pokemon available in the Pokedex, defeat all the gym leaders, then go to the Pokemon League to be the Champion League.

This game uses a region named Sinnoh. Your character will begin their adventure from a small town called Twinleaf Town. There you will meet your rival (whatever you name him to be), also you'll meet Professor Rowan, who will give you one of his pokemon, and his assistant (whichever gender you didn't choose).

This game is slightly different from the two other of this series, Pokemon Diamond and Pokemon Pearl. Even if they are from the same generation but there are slight differences here in Pokemon Platinum.

You can catch Giratina, a Dragon-Ghost Pokemon, at a world called Distortion World. If you did catch Giratina, it will appear to be in the alternate forme. to change it to its origin forme, you need the Griseous Orb to be held by Giratina. The orb itself can be found in the cave at the Spring Path after you defeat the Elite Four.

Unlike in Pokemon Diamond and Pearl, in this game you can catch BOTH Dialga and Palkia, the legendary of this series, at Spear Pillar after you defeat the Elite Four. be prepared though, both Dialga and Palkia will be at level 70 which is pretty tough. Palkia will have Spacial Rend, Heal Block, Earth Power, and Slash on his arsenal whereas Dialga has Roar Of Time with the same three moves as Palkia. Stock up your poke-balls, they won't be easy to catch. and don't forget to take the Adamant and Lustrous Orb in Mt. Coronet for catching Dialga and Palkia. Just like in Diamond and Pearl, the lake legendaries are also here for you to have, you can cath them after you defeat the villain Team Galactic.

Some Pokemon from the previous generation are also available here after defeating the Elite Four. So, you still have many things to do, like rebattle the gym leaders of Sinnoh with their much tougher Pokemon, then visit the Battle Frontier to battle and fill your pokedex, go to Stark Mountain to catch the remnants of Team Galactic and the Fire-Steel Pokemon, Heatran, in  his chamber deep in Stark Mountain.

reference : personal experience
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