My first competitively geared team ever. That may give you an idea of what to expect.
The only conditions are that, one, I wouldn´t like to use more than two TMs on one Pokémon due to their rarity and my plans on training many other critters (but do suggest it if you think it´s absolutely necessary), and two, if you propose that I replace one of my team members, please make the replacement a generation IV Pokémon. I´d like this team to be entirely Sinnoh.
Now, with that aside...
IZANAMI
Jolly Female (+ SPD, - SP ATK)
Pressure Ability (The foe uses 2 PP instead of 1 when attacking the user)
Holds Expert Belt (Slightly increases the power of super-effective attacks)
EV Spread - 40 HP / 252 ATK / 216 SPD
-- PURSUIT
-- ICE PUNCH
-- BRICK BREAK
-- AERIAL ACE
Many things loathe a Weavile to the point where they will gladly flee, which, when coupled with the possibilities of Pursuit, make Izanami a fine lead as far as I can see. Her primary roles would be to sweep with super-effective physical prowess and spook little children.
NANAKI
Modest Male (+ SP ATK, - ATK)
Steadfast Ability (The user´s SPD rises when it flinches)
Holds Choice Specs (Amplifies the power of Special moves, but only one move can be used)
EV Spread - 4 DEF / 252 SP ATK / 252 SPD
-- AURA SPHERE
-- DARK PULSE
-- DRAGON PULSE
-- PSYCHIC
A general Special sweeper with varied move typing to take care of anything in his way. I imagine that if a Togekiss with Flinch4x were to rear its neckless head, Lucario could switch in and receive a nice SPD boost with Steadfast, then hopefully KO it with Aura Sphere.
BLITZKRIEG
Adamant Male (+ ATK, - SP ATK)
Motor Drive Ability (Boosts the user´s SPD when hit by an Electric-Type attack)
Holds Muscle Band (Slightly increases the power of Physical attacks)
EV Spread - 4 HP / 252 ATK / 252 SPD
-- THUNDERPUNCH
-- CROSS CHOP
-- ICE PUNCH
-- EARTHQUAKE
The Choice Band could also be a neat idea for Blitzkrieg, although he scores super-effective hits on so many monsters that he´s probably better off with the Muscle Band. The basic plan is to oportunistically switch into a Thunderbolt or something to that effect and proceed to sweep.
GRIGORI
Impish Male (+ DEF, - SP ATK)
Hyper Cutter (The user´s ATK cannot be lowered)
Holds Shed Skin (The user is always able to switch out)
EV - 252 HP / 6 ATK / 252 DEF
-- KNOCK OFF
-- STEALTH ROCK
-- U-TURN
-- ROOST
Leftovers was Grigori´s original hold item, but if he is rendered unable to switch, his entire support-and-move-to-something-more-capable-of-mass-murder role would be demolished. Aside from that, there´s little else to say. He can knock troublesome items off, set Stealth Rock up for switch damage, Roost if so necessary, and U-turn the hell out. He´s also quite the Physical wall.
THANATOS
Careful Male (+ SP DEF, - SP ATK)
Pressure Ability (The foe uses 2 PP instead of 1 when attacking the user)
Holds Leftovers (Restored 1/16th of the user´s total HP each turn)
EV - 252 HP / 6 DEF / 252 SP DEF
-- WILL-O-WISP
-- TAUNT
-- PAIN SPLIT
-- SHADOW SNEAK
A Special wall, as well as the one to call in if an Explosion can be predicted. Thanatos can switch in with relative safety thanks to typing and defenses, then cripple Physical sweepers with Will-o-Wisp and annoy Walls or Baton Passer with Taunt. Pain Split could potentially bring him back from the brink of death, and Shadow Sneak is for the sake of having an attack move and in the case that moving first is imperative.
AGUNI
Modest Male (+ SP ATK, - ATK)
Flame Body Ability (Foes have a 30% chance of being burned if they make contact with the user)
Holds Hot Rock (Prolongs the number of turns that Sunny Day lasts to as long as eight)
EV Spread - 252 SP ATK / 176 HP / 80 SPD
-- FLAMETHROWER
-- SUNNY DAY
-- SOLARBEAM
-- THUNDERBOLT
Sunny Day powers up both Flamethrower and Solarbeam, the latter taking care of common elemental threats along with Thunderbolt. He´s a Special sweeper, I suppose, but I´m not sure if that implies I should be more generous with SPD in terms of EVs. Maybe the Choice Scarf is in order?
So, there it is. Be kind?
The only conditions are that, one, I wouldn´t like to use more than two TMs on one Pokémon due to their rarity and my plans on training many other critters (but do suggest it if you think it´s absolutely necessary), and two, if you propose that I replace one of my team members, please make the replacement a generation IV Pokémon. I´d like this team to be entirely Sinnoh.
Now, with that aside...

IZANAMI
Jolly Female (+ SPD, - SP ATK)
Pressure Ability (The foe uses 2 PP instead of 1 when attacking the user)
Holds Expert Belt (Slightly increases the power of super-effective attacks)
EV Spread - 40 HP / 252 ATK / 216 SPD
-- PURSUIT
-- ICE PUNCH
-- BRICK BREAK
-- AERIAL ACE
Many things loathe a Weavile to the point where they will gladly flee, which, when coupled with the possibilities of Pursuit, make Izanami a fine lead as far as I can see. Her primary roles would be to sweep with super-effective physical prowess and spook little children.

NANAKI
Modest Male (+ SP ATK, - ATK)
Steadfast Ability (The user´s SPD rises when it flinches)
Holds Choice Specs (Amplifies the power of Special moves, but only one move can be used)
EV Spread - 4 DEF / 252 SP ATK / 252 SPD
-- AURA SPHERE
-- DARK PULSE
-- DRAGON PULSE
-- PSYCHIC
A general Special sweeper with varied move typing to take care of anything in his way. I imagine that if a Togekiss with Flinch4x were to rear its neckless head, Lucario could switch in and receive a nice SPD boost with Steadfast, then hopefully KO it with Aura Sphere.

BLITZKRIEG
Adamant Male (+ ATK, - SP ATK)
Motor Drive Ability (Boosts the user´s SPD when hit by an Electric-Type attack)
Holds Muscle Band (Slightly increases the power of Physical attacks)
EV Spread - 4 HP / 252 ATK / 252 SPD
-- THUNDERPUNCH
-- CROSS CHOP
-- ICE PUNCH
-- EARTHQUAKE
The Choice Band could also be a neat idea for Blitzkrieg, although he scores super-effective hits on so many monsters that he´s probably better off with the Muscle Band. The basic plan is to oportunistically switch into a Thunderbolt or something to that effect and proceed to sweep.

GRIGORI
Impish Male (+ DEF, - SP ATK)
Hyper Cutter (The user´s ATK cannot be lowered)
Holds Shed Skin (The user is always able to switch out)
EV - 252 HP / 6 ATK / 252 DEF
-- KNOCK OFF
-- STEALTH ROCK
-- U-TURN
-- ROOST
Leftovers was Grigori´s original hold item, but if he is rendered unable to switch, his entire support-and-move-to-something-more-capable-of-mass-murder role would be demolished. Aside from that, there´s little else to say. He can knock troublesome items off, set Stealth Rock up for switch damage, Roost if so necessary, and U-turn the hell out. He´s also quite the Physical wall.

THANATOS
Careful Male (+ SP DEF, - SP ATK)
Pressure Ability (The foe uses 2 PP instead of 1 when attacking the user)
Holds Leftovers (Restored 1/16th of the user´s total HP each turn)
EV - 252 HP / 6 DEF / 252 SP DEF
-- WILL-O-WISP
-- TAUNT
-- PAIN SPLIT
-- SHADOW SNEAK
A Special wall, as well as the one to call in if an Explosion can be predicted. Thanatos can switch in with relative safety thanks to typing and defenses, then cripple Physical sweepers with Will-o-Wisp and annoy Walls or Baton Passer with Taunt. Pain Split could potentially bring him back from the brink of death, and Shadow Sneak is for the sake of having an attack move and in the case that moving first is imperative.

AGUNI
Modest Male (+ SP ATK, - ATK)
Flame Body Ability (Foes have a 30% chance of being burned if they make contact with the user)
Holds Hot Rock (Prolongs the number of turns that Sunny Day lasts to as long as eight)
EV Spread - 252 SP ATK / 176 HP / 80 SPD
-- FLAMETHROWER
-- SUNNY DAY
-- SOLARBEAM
-- THUNDERBOLT
Sunny Day powers up both Flamethrower and Solarbeam, the latter taking care of common elemental threats along with Thunderbolt. He´s a Special sweeper, I suppose, but I´m not sure if that implies I should be more generous with SPD in terms of EVs. Maybe the Choice Scarf is in order?
So, there it is. Be kind?