I haven't played Sun/Moon competitive yet, so this set probably doesn't work there but here is my x/y doubles team;
Main Attacker, M-Gyarados (Crunch, aqua tail, dragon dance, dragon something phys move)
Support attacker, Raichu with focus sash. Maximum speed. Thunder, tbolt, nuzzle, nasty plot.
Defense. Chestnaught. Spikey shield, wood hammer, toxic, leech seed. Sometimes left overs, sometimes rock helmet.
But my "underrated fun build" is my Raichu and Gyarados bff. Crobat!
"Crobat? Anon you fucking retard that thing is decent."
Yeah well, my crobat is;
DEFENSE HP AND SPEF EVs holding a ...DAMP. ROCK!
"Anon are you a ret-"
Sometimes. But listen. My crobat knows Rain dance, Roost, HYPNOSIS, and bravest bird.
Roost for healing, obviously since it's kinda beefy. Brave bird for damage and coverage. Hypnosis and it's BASE speed make it one of the FASTEST hypnosis users and...well yeah it can miss. But it's saved me a bunch of times. If it hits, it buys at LEAST one turn for Gyarados or Raichu to start cleaning house.
Turn 1 is almost always Dragon dance - Rain dance w/ crobat and gyarados. If they have something electric I obviously switch to lightning rod Raichu. Anything that might ohko my Gyarados or put a nasty status on it, I go for hypnosis instead.
Turn 2 is either M-gyarados time or another DD if it's safe. Crobat can either rain dance or hypnosis. The only time I'm not spamming hypnosis is if he can help KO things with bravest bird or he needs to heal.
They never aim for Crobat, so when it's down, I'm free to toss in Raichu for 100% accurate Thunder. I really love when I predict an electric move, throw out Raichu and get the +1 boost, then next turn nasty plot for a total of +3 and then just clean house with a rain dance boosted thunder. Otherwise m-gyarados can sweep with aqua tail after being boosted once or twice with DD. Chestnaught is for phys pokemon it can stall out w/ crobat.
