The following are suggestions for your team (for Platinum Metagame):
First off I would like to say the Uber environment is far different than the OU environment, if you didn't know that already.
Arceus- Make it Adamant. The loss SDef is unnecessary, and you need all the SDef in the Uber environment you can get. If you cannot stand losing the SAtk, make it Lonely.
Also, trade Poison Jab for any other attack. Poison's type coverage is the worst in the game, and there are far more powerful moves out there available for Arceus. Outrage with it holding a Dragon Plate will make it as dangerous as Garchomp. Stone Edge is fine. EQ, you could and should change it to Shandow Claw, as a vast majority of the Uber Metagame is hit for Super Effective Damage.
Dialga- Change Roar of Time and Flash Cannon for Aura Sphere and Magnet Rise. Flash Cannon's type coverage is not that much better than Poison Jab. Roar of Time, while it is one of the strongest attacks in the game, will be out damaged by Draco Meteor over the course of two turns, and by Dragon Pulse over the course of 4 turns. Also, you do not need 2 moves of the same type in the same moveset, barring a Draco Meteor Specs set.
Groudon- Use Stone Edge over Dragon Claw or Shadow Claw. They both have uses important to the Ubers, but Ho-oh, Lugia, and Rayquaza are all imperiled by a Stone Edge. I would normally ask you to change the nature, but if you are using Impish to block some dominant physical sweepers and hit them hard, great. If not, use Adamant over Impish. Also, change the Item from Spell Tag to a Life Orb. Groudon is stable enough to take a hit, and it adds a x1.3 boost to all attacks, not just a x1.2 boost to Ghost Attacks.
Rayquaza- Change fly for something else. Although it is powerful, it allows the opponent to switch to a counter while he is in the air, and hit him hard when he comes down. Earthquake is the way to go.
Deoxys- I cannot help you unless I know the Form. I'm guessing it is Deoxys-A by the moveset. Change Serious to Hasty for speed and give it the Life Orb. It will not have long to live, as a single weak hit will OHKO.
Change Brick Break to Superpower, as it will 2KO Blissey, which is the only major threat to this moveset. Change Psychic to HP Fire or Shadow Ball, as it will have more type coverage in the Ubers than Psychic will.
Giratina- Is a waste of the best Sleep Talker in the game. The best moveset IMO is:
- Calm Mind
- Rest
- Sleep Talk
- Dragon Pulse
Item: Leftovers
Nature: Bold
EVs: 252 HP / 252 Def / 6 SAtk
This appears to be basic. CM up until you have 2 turns of life left, Rest, use Sleep Talk, attack while you sleep, attack with Dragon Pulse after you wake up. It will cause mega damage after 4 CMs.
Other Stuff- Stealth Rock is seldom seen in the Ubers. If you want to surprise your opponents, change Deoxys-A to Deoxys-S. Not only will Deoxys-S be able to stop the famous Deoxys-A, it will also set up Stealth Rock, which few teams will be able to spin away.
I have noticed you do not know about EVs, or you just did not post them. They will allow your pokemon's stats to be up to 63 points higher, which makes a big difference.
Read LP's Article on Training and you will learn an important part of Pokemon. Even though it is geared for RSE, EVs did not change over the generation shift, so it is not a concern.
If you want my recommended EV spreads, just ask or PM me.
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