My Dream Team (may not be so dreamy)

[Redingard]

So, new to competitive battling. Never did it before Generation 6. So, naturally, I only want to use my favorite Pokemon. xD

Slot one: Greninja, Modest, Protean, 252 EVs in Sp. Atk and Speed

Extrasensory
Surf
Dark Pulse
Ice Beam

Slot Two: Electivire, Adamant, Vital Spirit, 252 EVs in Attack and Speed

Thunder Wave
Earthquake
Wild Charge
Ice Punch

Slot Three: Gengar, Modest, 252 Evs in Sp. Atk and Speed (holds Gengarite)

Sludge Bomb
Dazzling Gleam
Dark Pulse
Shadow Ball

Slot Four: Charizard, Adamant, 252 EVs in Attack and Speed (may or may not hold Charizardite X)

Dragon Claw
Flare Blitz
Swords Dance
Earthquake

Slot 5: Slyveon

Not sure to do with this one yet. I don't even have it, but I know it can be a great Sp. Def Wall. I might have it distract the other team with stuff like Encore and Taunt, and have Dazzling Gleam for its only Attack move.

Slot 6: Sceptile (when Pokebank comes out)/Shiftry, 252 EVs in Attack and Speed

Foul Play
Bullet Seed
Brick Break
Rock Slide

No idea how good this team would perform in a real battle.

 

[PlatinumDude]

Greninja must be Timid. With Modest, it fails to outspeed Dugtrio, Alakazam, etc. Extrasensory is good for in-game runs sure, but it's not so hot competitively:
-Hydro Pump/Surf
-Dark Pulse
-Ice Beam
-U-turn/Hidden Power (Fire)
Nature: Hasty/Timid
EVs: 4 Atk/252 SAtk/252 Spe
Item: Life Orb

Electivire is terrible in standard because of the low base power of its coverage moves. While Wash Rotom shares a Grass weakness with Greninja (though Greninja can get rid of it with Protean), it's the better option:
-Volt Switch
-Hydro Pump
-Will-o-Wisp
-Rest
Nature: Bold
EVs: 252 HP/252 Def/4 SAtk
Item: Chesto Berry

or
-Discharge
-Volt Switch
-Hydro Pump
-Hidden Power (Ice)
Nature: Modest
EVs: 232 HP/56 SAtk/220 Spe
Item: Assault Vest

or
-Volt Switch
-Hydro Pump
-Hidden Power (Ice)
-Trick/Thunderbolt
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Choice Scarf/Choice Specs

Dark Pulse and Shadow Ball have redundant coverage with one another. Never use Dark moves on a Ghost unless: 1. it's Spiritomb, who utilizes Pursuit and/or Sucker Punch to trap Psychics and other Ghosts, 2. it's Mega Banette, who uses Knock Off to remove items or Sucker Punch for strong priority and 3. it's Sableye, who sometimes uses Foul Play as an offensive move. Remember that physical Charizard is terrible unless it holds Charizardite X, so Gengar must make do without Gengarite:
-Shadow Ball
-Sludge Bomb
-Focus Blast/Hidden Power (Fire)
-Substitute/Protect
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Life Orb/Black Sludge

or
-Shadow Ball
-Sludge Bomb
-Focus Blast
-Hidden Power (Ice)/Thunderbolt/Trick
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Choice Scarf

Charizard X should use Dragon Dance because while 100 Speed isn't bad it's not too good either.

Sylveon can run Wish or Calm Mind. Your pick:
-Wish
-Protect
-Moonblast
-Shadow Ball/Hidden Power (Fire)
Nature: Bold
EVs: 252 HP/252 Def/4 SDef
Item: Leftovers

or
-Calm Mind
-Moonblast
-Shadow Ball
-Hidden Power (Fire)
Nature: Modest
EVs: 252 HP/252 SAtk/4 Spe
Item: Leftovers

These Sceptile sets should be used only if Poke Bank comes out:
-Substitute
-Giga Drain
-Focus Blast
-Hidden Power (Rock)
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Life Orb
Ability: Overgrow

or
-Leaf Storm
-Giga Drain
-Focus Blast
-Hidden Power (Rock)
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Choice Specs/Life Orb
Ability: Overgrow

or
-Swords Dance
-Leaf Blade
-Earthquake/Drain Punch
-Rock Slide
Nature: Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Life Orb

Also, Shiftry is absolutely useless outside of sun. Bullet Seed is unreliable unless it's used by Breloom (who has Technician), Cinccino and Mega Heracross (the latter two have Skill Link). Make do with Ferrothorn or Chesnaught:

Ferrothorn:
-Spikes/Stealth Rock
-Leech Seed
-Power Whip/Protect
-Gyro Ball/Thunder Wave
Nature: Relaxed
EVs: 252 HP/208 Def/48 SDef
Item: Leftovers
Ability: Iron Barbs

Chesnaught:
-Spikes
-Synthesis
-Hammer Arm
-Stone Edge/Roar/Leech Seed
Nature: Impish
EVs: 252 HP/4 Atk/252 Def
Item: Leftovers
Ability: Bulletproof