This one is for DOUBLES, but maybe it can be used anyway.
This team abuses pokemon that have extremely terrible typing, speed, and movepools but have one or two outlandishly powerful attributes. These pokemon would never be usable in single battles, as they would get immediately wrecked by much more powerful and fast pokemon. But thanks to the 2v2 nature of doubles and key moves like Fake Out, in doubles you are practically guaranteed to be able to successfully use Trick Room. Thanks to Battle Spot being only 4v4 instead of 6v6, a couple Pokemon with outlandishly powerful moves can often sweep the entire enemy team before Trick Room wears off!
This is not the sort of team that works more than once. Generally, if an opponent knows what you are doing, they should be able to counter it. But for a one-off match versus an unprepared opponent, you can achieve surprisingly good results with hilariously obscure Pokemon.
THE LEADS:
Blastoise @Blastoisinite
Quiet, 252 HP / 4 Def / 252 SpAtk
Fake Out
Water Pulse
Dark Pulse
Aura Sphere
Blastoise must be picked first in every single battle. You use Fake Out to disable one of the two enemy mons, so you can get Trick Room off. The rest is just support.
This slot can technically be filled with any Fake Out user that has a reasonably low speed stat. For a while, I was even using Mega Medicham -- eventually I replaced him for Blastoise because I felt that Medicham was too strong on his own, thus defeating the whole point of the team! The less used and more obscure the Pokemon, the better.
Lunatone
Focus sash
Quiet, 252 SpAtk
Trick Room
Psychic
Ice Beam
Will-o-Wisp / Explosion
One of two Trick Room users. Pick Lunatone most times -- when you think your opponent is just going to attack, attack, attack, and need to simply survive the first turn so you can get Trick Room off.
After Trick Room, you can utilize Lunatone's almost-acceptable base 95 Special Attack to fire off some attacks. Or you could Explode to simply get her out of the way. Will-o-Wisp can cover some Shedinja gimmicks, if you'd prefer; it's not like Explosion off of the base 55 Attack is going to be doing much damage.
Beheeyem
Lum Berry
Quiet, 252 HP / 252 SpAtk
Trick Room
Psychic
Ice Beam
Signal Beam
The other Trick User, to be used whenever you think your opponent's openers will attempt to status you. Beheeyem is reasonably obscure and has an extremely respectable base 125 Special Attack, so at least his attacks will hurt. He can't learn Explosion though; if you're after that, try something like Exeggutor (who also gets a grass STAB, if it matters).
THE CAVALRY:
Camerupt
Life Orb
Quiet, 252 HP / 4 Atk / 252 SpAtk
Eruption
Earth Power
Stone Edge
Protect
Camerupt is, in most respects, an awful Pokemon. His attacking stats (100 / 105) are horrible for a sweeper, he's slow, and his defensive typing is horrible. But there is a saving grace, that makes him perfect for our team of obscure Pokemon! He learns a 150-power fire attack that he gets STAB on and hits both opponents! Eruption is hideously powerful and is capable of wiping both opponents. You won't be able to spam it thanks to Life Orb, but just once will get the job done.
Rampardos @Sitrus Berry
Mold Breaker
Brave, 252 HP / 252 Atk
Head Smash
Hammer Arm
Crunch
Earthquake
Man, this guy is rough. Absolutely horrible stats and an awful mono-rock typing, but check out that attack! Plus, a 150 power STAB attack! Rampardos isn't about to be rocking OU any time soon, but it sure is high on the obscure list. The raw power available makes him usable for our purposes.
Mold Breaker Earthquake can be used if it's absolutely needed, but you're almost always better just Head Smashing away. Rampardos is the definition of one-trick pony.
Octillery
Expert Belt
Sniper
Quiet, 252 HP / 252 SpAtk
Water Spout
Energy Ball
Ice Beam
Hydro Pump
Octillery is a lot like Camerupt with different typing. Like Camerupt, it has average-to-good attacking stats (105/105). Like Camerupt, the rest of its stats are mediocre. Like Camerupt, it's reasonably obscure. And like Camerupt, it has a base 150 power STAB attack that hits both opponents. Hydro Pump is for when your HP is low and you need single targeting, and Energy Ball deals heavy damage to Rotom-W.
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Well, that's the team. I'm sure you can come up with your own variation. There are plenty of stronger Pokemon that could be used in their places, but remember the ultimate goal: beat extremely overused and uber Pokemon with hilariously obscure and neverused Pokemon!
