After the release of the May Server Stats, I decided to create a team that can counter most of OU's major threats. A difficult task, even I admit, especially with the prevelence of Stealth Rock to damage switch-ins.
Changes from the Original are in Red
Well, after much thinking, I came across a lead that can defeat ALL of the 'Big 12' leads, with these 12 combined having 50% of the total lead useage.
The Anti-Lead
Modest Nature
Choice Specs
252 Sp.A / 252 Spe / 4 HP
Thunderbolt
Trick
Shadow Ball
Leaf Storm
I calculated damage on all of the standard lead sets for the 'big 12' barring Ninjask, who is OHKO'ed by most things, and has Sash anyway, and the results were pleasing. Please note that these are in useage order.
Metagross: Thunderbolt = 66.76% - 78.57% (Outsped)
Azelf: Thunderbolt = 192.72% - 226.44% (Sashed, but can't 2HKO)
Swampert: Leaf Storm = 237.16% - 279.05% (Outsped)
Jirachi: Thunderbolt = 58.53% - 68.77%
Aerodactyl: Thunderbolt = 186.75% - 219.54% (Sashed, but can't 2HKO)
Infernape: Thunderbolt = 100.34% - 118.09%
Hippowodon: Leaf Storm = 110.24% - 129.76% (Outsped)
Ninjask: Thunderbolt = 2HKO due to Sash
Bronzong: Thunderbolt = 53.85% - 63.31% (Outsped)
Tyranitar: Leaf Storm = 91.27% - 107.23% (Outsped)
Heatran: Thunderbolt = 65.43% - 77.16% (Outsped without + Speed)
Abomasnow: Shadow Ball = 66.98% - 78.82% (Outsped)
As you can see, only Metagross, Jirachi, Heatran, Abomasnow and Bronzong are not OHKO'ed (Tyranitar CAN live), and of these, only Heatran and Abomasnow can do anything significant back, unless Jirachi flinchaxes it's way past. Rotom is immune to Explosion, that so many Suicide leads carry, and also Fighting types, and EQ. Rotom is bulky enough to take a hit or two with it's inferior speed, barring possibly Tyranitar, and KO the lead back, especially as most will either set up rocks, or switch. In the event of a switch, anything that is not a Ground type will take a heavy blow from Thunderbolt, those who are not Normals will be hurt by Shadow Ball, and Leaf Storm brings the pain on almost anything else not with a X4 resist.
Bronzong, although a possible 3HKO due to lefties, can hardly scratch Rotom, due to it's low speed, and resistance to Gyro Ball, and Immunity to Explosion and Earthquake. Same with Metagross's Meteor Mashes.
Basically, Rotom can stop about half of the common leads from setting up Rocks, and score a OHKO on half of them as well.
I then thought about Rotom's common switch-ins. Normal types to cushion Shadow Balls, Steels for Leaf Storms and Shadow Balls. Which pokemon can take both of those types on...
Mild Nature
Life Orb
64 Atk / 252 SpA / 192 Spe
Flamethrower
Close Combat
Hidden Power Ice
Grass Knot
Yep, it's a Specially Based MixApe! Not only great for cracking stall teams wide open, and killing Scizors, non-scarfed Heatrans, Skarmbliss, ect, but also great for dealing with Rotom Counters! The likes of Snorlax and Blissy will run away at the sight of this thing, as will most Steel Types. In come the dragons or Bulky Waters, to be Knotted or HP Iced as I need.
Mild is chosen because Infernape's main physical threat is Earthquake, something that can be sponged by Rotom, or other flyers on my team.
Timid Nature
Leftovers
Natural Cure
136 HP / 156 Sp.A / 216 Spe
Rapid Spin
Surf
Thunderbolt
Recover
A Spinner Starmie... or is it? Sure, Starmie does Spin, it's arguably the best in OU at that job. However, Starmie also rids of those pesky Ground Types who just want to come in on Rotom's predicted Thunderbolts at the start of the game. Surf deals with most of them. Recover helps with general bulkyness, and allows multiple switch-ins on things that are forced out, with Starmie being able to take the switch-in attack, and recover on the switch-out of it's foe. Spin clears the way for my lategame sweepers. Starmie also plays the role of drawing Electric Attacks in the Midgame...
Naughty Nature
Choice Scarf
80 HP / 252 Atk / 176 Spe
Outrage
Earthquake
Fire Blast
U-Turn
Scarfgon loves to come in on an Electric Attack, free switch-in, after all, and the Electric type goes running to something that flys. If I know that there is something like Bronzong on their team, Fire Blast shall be the option. Earthquake is for when I KNOW that there are no flyers. Outrage is for when I expect something like a Salamance, or, I come in on a locked Dragon, outspeed, and OHKO. U-Turn is for scouting, after all, if I don't know what's coming, I can't select any move. Fire/Dragon/Ground is unresisted. Naughty over Adamant because I'm using Fire Blast.
Bold Nature
Trace
Leftovers
252 HP / 216 Def / 40 SpA
Thunderbolt
Ice Beam
Recover
Thunder Wave
Porygon 2 fits it's description in the 'defensive duck' section of it's suggestions. Heatran, Salamance, Jolteon, Garados, Vaporeon, Electrivire, Magnezone, Gengar (To some extent), the list goes on and on of the pokemon Porygon 2 can counter. It takes little short of a Fighting-Type Attack to OHKO this thing, and Recover and Thunder Wave make it very hard to KO unless it's done in one Hit. For this role of 'Garados and Jolteon counter' I had to choose between Gardevoir giving me another Ghost Weakness, or this little guy, giving me a Ghost Immunity.
Basically, as well as countering several big names, this guy provides good synergy, and support.
Bold Nature
Leftovers
252 HP / 220 Def / 36 Spe
Thunderbolt
Heat Wave
Roost
Hidden Power Grass
Zapdos provides one of the best checks against most Steel and bulky-water pokemon, while filling a unique niche as a 'Bulky Electric' with a reliable recovery move, namly Roost. Zapdos is a threat in terms of power in it's own right, and I often save Zapdos for when I need it, and Stealth Rock is ridden, or, for the late-game, leaving my foes blissfully unaware of this monster lurking in my team. Fire+Grass+Electric is a rather good attacking combination, with very few pokemon resisting the entire combination, namly Latias, Latios, and the Pure Dragons (All of which are NFE). Zapdos is very hard to stop when Porygon 2 has spread Thunder Waves, and Rotom/Starmie have killed Ground/Rock types.
So, what do you think?
Changes from the Original are in Red
Well, after much thinking, I came across a lead that can defeat ALL of the 'Big 12' leads, with these 12 combined having 50% of the total lead useage.
The Anti-Lead

Modest Nature
Choice Specs
252 Sp.A / 252 Spe / 4 HP
Thunderbolt
Trick
Shadow Ball
Leaf Storm
I calculated damage on all of the standard lead sets for the 'big 12' barring Ninjask, who is OHKO'ed by most things, and has Sash anyway, and the results were pleasing. Please note that these are in useage order.
Metagross: Thunderbolt = 66.76% - 78.57% (Outsped)
Azelf: Thunderbolt = 192.72% - 226.44% (Sashed, but can't 2HKO)
Swampert: Leaf Storm = 237.16% - 279.05% (Outsped)
Jirachi: Thunderbolt = 58.53% - 68.77%
Aerodactyl: Thunderbolt = 186.75% - 219.54% (Sashed, but can't 2HKO)
Infernape: Thunderbolt = 100.34% - 118.09%
Hippowodon: Leaf Storm = 110.24% - 129.76% (Outsped)
Ninjask: Thunderbolt = 2HKO due to Sash
Bronzong: Thunderbolt = 53.85% - 63.31% (Outsped)
Tyranitar: Leaf Storm = 91.27% - 107.23% (Outsped)
Heatran: Thunderbolt = 65.43% - 77.16% (Outsped without + Speed)
Abomasnow: Shadow Ball = 66.98% - 78.82% (Outsped)
As you can see, only Metagross, Jirachi, Heatran, Abomasnow and Bronzong are not OHKO'ed (Tyranitar CAN live), and of these, only Heatran and Abomasnow can do anything significant back, unless Jirachi flinchaxes it's way past. Rotom is immune to Explosion, that so many Suicide leads carry, and also Fighting types, and EQ. Rotom is bulky enough to take a hit or two with it's inferior speed, barring possibly Tyranitar, and KO the lead back, especially as most will either set up rocks, or switch. In the event of a switch, anything that is not a Ground type will take a heavy blow from Thunderbolt, those who are not Normals will be hurt by Shadow Ball, and Leaf Storm brings the pain on almost anything else not with a X4 resist.
Bronzong, although a possible 3HKO due to lefties, can hardly scratch Rotom, due to it's low speed, and resistance to Gyro Ball, and Immunity to Explosion and Earthquake. Same with Metagross's Meteor Mashes.
Basically, Rotom can stop about half of the common leads from setting up Rocks, and score a OHKO on half of them as well.
I then thought about Rotom's common switch-ins. Normal types to cushion Shadow Balls, Steels for Leaf Storms and Shadow Balls. Which pokemon can take both of those types on...

Mild Nature
Life Orb
64 Atk / 252 SpA / 192 Spe
Flamethrower
Close Combat
Hidden Power Ice
Grass Knot
Yep, it's a Specially Based MixApe! Not only great for cracking stall teams wide open, and killing Scizors, non-scarfed Heatrans, Skarmbliss, ect, but also great for dealing with Rotom Counters! The likes of Snorlax and Blissy will run away at the sight of this thing, as will most Steel Types. In come the dragons or Bulky Waters, to be Knotted or HP Iced as I need.
Mild is chosen because Infernape's main physical threat is Earthquake, something that can be sponged by Rotom, or other flyers on my team.

Timid Nature
Leftovers
Natural Cure
136 HP / 156 Sp.A / 216 Spe
Rapid Spin
Surf
Thunderbolt
Recover
A Spinner Starmie... or is it? Sure, Starmie does Spin, it's arguably the best in OU at that job. However, Starmie also rids of those pesky Ground Types who just want to come in on Rotom's predicted Thunderbolts at the start of the game. Surf deals with most of them. Recover helps with general bulkyness, and allows multiple switch-ins on things that are forced out, with Starmie being able to take the switch-in attack, and recover on the switch-out of it's foe. Spin clears the way for my lategame sweepers. Starmie also plays the role of drawing Electric Attacks in the Midgame...

Naughty Nature
Choice Scarf
80 HP / 252 Atk / 176 Spe
Outrage
Earthquake
Fire Blast
U-Turn
Scarfgon loves to come in on an Electric Attack, free switch-in, after all, and the Electric type goes running to something that flys. If I know that there is something like Bronzong on their team, Fire Blast shall be the option. Earthquake is for when I KNOW that there are no flyers. Outrage is for when I expect something like a Salamance, or, I come in on a locked Dragon, outspeed, and OHKO. U-Turn is for scouting, after all, if I don't know what's coming, I can't select any move. Fire/Dragon/Ground is unresisted. Naughty over Adamant because I'm using Fire Blast.

Bold Nature
Trace
Leftovers
252 HP / 216 Def / 40 SpA
Thunderbolt
Ice Beam
Recover
Thunder Wave
Porygon 2 fits it's description in the 'defensive duck' section of it's suggestions. Heatran, Salamance, Jolteon, Garados, Vaporeon, Electrivire, Magnezone, Gengar (To some extent), the list goes on and on of the pokemon Porygon 2 can counter. It takes little short of a Fighting-Type Attack to OHKO this thing, and Recover and Thunder Wave make it very hard to KO unless it's done in one Hit. For this role of 'Garados and Jolteon counter' I had to choose between Gardevoir giving me another Ghost Weakness, or this little guy, giving me a Ghost Immunity.
Basically, as well as countering several big names, this guy provides good synergy, and support.

Bold Nature
Leftovers
252 HP / 220 Def / 36 Spe
Thunderbolt
Heat Wave
Roost
Hidden Power Grass
Zapdos provides one of the best checks against most Steel and bulky-water pokemon, while filling a unique niche as a 'Bulky Electric' with a reliable recovery move, namly Roost. Zapdos is a threat in terms of power in it's own right, and I often save Zapdos for when I need it, and Stealth Rock is ridden, or, for the late-game, leaving my foes blissfully unaware of this monster lurking in my team. Fire+Grass+Electric is a rather good attacking combination, with very few pokemon resisting the entire combination, namly Latias, Latios, and the Pure Dragons (All of which are NFE). Zapdos is very hard to stop when Porygon 2 has spread Thunder Waves, and Rotom/Starmie have killed Ground/Rock types.
So, what do you think?