Background Information:
I wanted to make a new team with the Platinum releases, but not too devoted to countering the new threats. I attempted to make a team that synergized well, and it won 9 out of 10 games when I just started testing (the loss due to stupid prediction to a BP team). I also wanted to make a team that was workable with the few guys I was breeding for Wi-Fi.
At a glance:
A
In-depth:
Mesprit @ Leftovers
Nature: Bold (+Def -Atk)
Ability: Levitate
EVs: 252 HP / 68 Def / 92 Sp. Atk / 96 Sp. Def
Stealth Rock
Thunderbolt
Ice Beam
Water Pulse
I was originally opposed to using a Stealth Rock lead, considering it's generally a suicide lead and a Rapid Spinner just kills it's purpose. However, in the current metagame you never see Rapin Spinners, so I figured "what the hell" and went with a SR/non-suicide lead. Thunderbolt covers Gyarados leads, Ice Beam for Salamence and Skymin (if I ever ran into one that didn't flinch me). Water Pulse covers Infernape mostly, and it might be replaced with Psychic to serve the same purpose but with more power. It's hard to give up the 20% chance to confuse, though.
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Gallade @ Choice Scarf
Nature: Jolly (+Spe -Sp. Atk)
Ability: Steadfast
EVs: 4 HP / 252 Atk / 252 Spe
Thunderpunch
Close Combat
Psycho Cut
Ice Punch
Revenge killer, and a good one at that. Thunderpunch and Ice Punch mainly for the same thing reasons as Mesprit's Thunderbolt/Ice Beam, and he outspeeds both after 1 DD. Close Combat for huge damage, and Psycho Cut for Gengar mostly. This was originally a Hitmonchan, but other than the Ghost weakness, Gallade does everything Hitmonchan can do better.
*May replace Psycho Cut with Night Slash for Gengar, as well as other Ghosts.
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Muk @ Black Sludge
Nature: Careful (+Sp. Def -Sp. Atk)
Ability: Sticky Hold
EVs: 252 HP / 80 Def / 176 Sp. Def
Curse
Ice Punch
Brick Break
Poison Jab
Muk is an interesting Pokémon. 105/75/100 base Defenses make him a good special wall, but with Curse he also has the ability to be a physical wall. He can switch in on most special attacks as well as NVE physical ones, Curse up and possibly sweep. Sticky Hold makes him immune to Trick, and he absorbs Toxic/Toxic Spikes well.
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Celebi @ Leftovers
Nature: Bold (+Def -Atk)
Ability: Natural Cure
EVs: 252 HP / 220 Def / 36 Spe
Grass Knot
Leech Seed
Heal Bell
Recover
Replaced Meganium. Physicall wall. Celebi is my only answer to Swampert, bar Heatran who cannot safely switch into him anyways. Leech Seed and Recover provide great survivability, and Heal Bell to support my sweepers who absolutely hate certain statuses.
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Heatran @ Choice Specs
Nature: Timid (+Spe -Atk)
Ability: Flash Fire
EVs: 4 HP / 252 Sp. Atk / 252 Spe
Lava Plume
Earth Power
Dragon Pulse
Hidden Power [Grass]
Funny thing about Heatran now-a-days: he can switch into Scizor/Skymin and force them to switch out without even sporting a Scarf. Earth Power is a 2HKO on Scizor, and if you're not sure about opposing Heatran, it's a safe move to take. Unfortunately, if you mispredict Lava Plume/Earth Power on Skymin you're forced to switch out or die. Still, Lava Plume off of 537 Sp. Atk is something you don't want to get hit with. HP Grass for Swampert/Suicune switch-ins, Dragon Pulse for Dragons.
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Hitmontop @ Leftovers
Nature: Impish (+Def -Sp. Atk)
Ability: Technician
EVs: 252 HP / 72 Def / 184 Spe
Mach Punch
Rapid Spin
Toxic
Aerial Ace
Rapid Spinner, because it's not expected as much in today's metagame. Counters Heracross and has priority to take care of things late-game. Toxic to cripple walls that think they can take Hitmontop's meager attacks.
*Replace Mach Punch with Bullet Punch? STAB + Technician vs. hitting Ghost-types.
**May make him more Sp. Def oriented, as not much of my team can take special hits bar Muk and NVE moves to Heatran/Gallade.
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Outro:
I generally try to play off of my opponents mistakes and team synergy. The team is much more geared towards being balanced both offensively as well as defensively, providing support for the sweepers (Gallade and Heatran, mostly). All comments are welcome; If there is a gaping hole in my team feel free to point it out to me and how I can fix it.