Welcome to the -cruel world of- competitive game ! Yeah,I know, this is a cruel world where you have to stand up against those stupid rules (Sleep Clause, Species clause ...) So I hope you will do better with my rate :D Also your team's looking as an OU one, so I can help more, I know the best this domain between the domains I know.
OK, let's start:
Jolteon is an excellent Electric sweeper, in OU. So I will recommend you to keep it. I have made for every Pokemon the changes in Bold, OK ?
Jolteon (M) @ Choice Specs:
Trait: Volt Absorb
EVs: 252 SAtk / 4 HP/ 252 Spd
Timid Nature (+Spd, -Atk)
- Shadow Ball
- HP [ HIDDEN POWER ICE]
- Signal Beam / Volt Switch
Let's begin: The Specs allows to hit harder, and Jolteon's HP are stronger than Defense, that's why I changed this. Hidden Power [ICE] is essential to every Electric Sweeper, because of the 2 coverage (Grass and Ground). And the last slot really depends on your preference to hit Dark and Psychic Pokemon or to scout (that I recommend).
Gengar is another great Special sweeper in OU, that's why you must keep it.
Gengar (M) @ Focus Sash
EVs: 252 SAtk / 4 HP / 252 Spd
Timid Nature (+Speed, -Atk)
- Focus Blast
- Shadow Ball
- Giga Drain
- Sludge Bomb
OK, let's begin: For the same reasons as Jolteon, I changed your EV (that you could forget, no problems of course). Gengar's terribly strong sp.ATK doesn't need much boosting, contrarily to his speed so Timid works more for it. Giga Drain can be used in case of recovery against SR (Stealth Rock) and Sludge Bomb is for the strong STAB.
You need a sweeper, and Breloom assumes this job.
Why ? Because Breloom can spore foes and then it can boost, making it very strong. The problem called Trollkazam is solved due to Sash Gengar.
And to stall up, no probs, we will remove Haxorus later.
Breloom @ Life Orb:
EVs: 252 Attack / 128 SPE / 128 HP
- Swords Dance
- Bullet Seed
- Mach Punch
Life Orb and Technician are to ensure hard-hitting. The EV spread gives at the same time a bulky entry and a sweeper force, but with not so much speed supported by Jolly nature.
Spore asleep opponents, so the time to swords 1 or 2 times and then to smash everything !
That thing is strong enough to smash most of the OU threats, Blissey first.
Bullet Seed and Mach Punch are ... strong ? ( lol of course yes :D )
Dragonite is with those pseudo-legendary Pokemon, and so with its high stats and average speed it is strong enough to smash things that the rest of the team doesn't like (Garchomp, for example).
Dragonite (M) @ Lum Berry
EVs: 252 Atk / 4 HP / 252 HP
Adamant Nature (+Atk, -SAtk)
- Fire Punch
- Dragon Claw
- Dragon Dance
Quite basic. The Lum berry is used over your Muscle band (for which I applause the originality) because if you get burned, you are ruined. DD Dragonite is one of the strongest. The HP EV can be ignored. Dragon Claw must be here, for the accuracy, because I'm sure that you will miss 1/4 of the time Dragon Rush but not Dragon Claw, yet weaker a bit, but worthier, believe me.
I said it, 2 dragons are strong, but you NEED a wall.
Ferrothorn is this wall, with both good defensive and Hazards to setup, that's excellent.
I won't explain more, let's go for the moveset.
Ferrothorn @ Rocky Helmet:
Trait: Iron Barbs
EVs: 252 HP / 128 DEF / 128 sp.DEF
IV: 0 Speed
- Gyro Ball
- Stealth Rock
- Leech Seed
Ability and item are for rear damages, while IV and EV gives both a good Bulk and a strong Gyro Ball. Stealth Rock and Spikes for Hazard and finally Leech Seed for annoyance.
Tentacruel over Lapras, let's see why
You know, in that terrible world, SR and Hazards are so common that you need a rapid spinner, and by respecting your choice of a water type Pokemon, Tentacruel is here, and is more useful than you think. Why ? Let' see !
Tentacruel @ Black Sludge:
Trait: Rain Dish
EVs: 252 HP / 252 Speed / 4 sp.ATK
- Toxic Spikes
- Rain Dance
- Rapid Spin
This is an excellent core, Ferrocruel ! Ferrothorn launches hazards and Leech Seed and then is withdrawn for Tentacruel, that lunches Toxic Spikes and Rain Dance and restores per turn 1/4 of its HP, which is excellent, of course with Rain Dish so Rain Dance. Rapid Spin eliminates hazard against you, and finally Scald is to hit quite hard, and to burn those Conkeldurr.
Wish I helped ! Arcanine also wishes this :D
"Good Luck with my master's rate :D"