Umbreon @ Leftovers
Synchronize
Impish
-Toxic
-Moonlight
-Confuse Ray
-Pursuit
A basic kill-with-toxic Umbreon, but instead of mean look to trap them i just confuse, toxic, and spam STAB pursuit, so if they try to switch out they take a decent chunk of damage while still being badly poisoned.

Gengar @ Choice Specs
Levitate
Timid
-Shadow Ball
-Thunderbolt
-Focus Blast
-Trick
No explanation needed tbh.

Absol @ Razor Claw
Super Luck
Adamant
-Night Slash
-Psycho Cut
-Stone Edge
-Swords Dance
Razor Claw and Super Luck stack with it's movepool's already high crit chance, and if it can manage to get in 3 swords dances it can OHKO pretty much anything, especially with the high crit.

Dusknoir @ Leftovers
Pressure
Impish
-Will-O-Wisp
-Pain Split
-Fire Punch
-Shadow Sneak
Makes a very nice physical tank with will-o-wisp, and can hold its ground against special sweepers well enough. Pain Split is a very nice healing move when used at the right time, and fire punch and STAB shadow sneak are just basic filler.

Houndoom @ Expert Belt
Flash Fire
Timid
-Flamethrower
-Dark Pulse
-Hidden Power (fighting)
-Nasty Plot
Basic special sweeper; switch in on a predicted fire attack and use nasty plot while the foe (most likely) switches out.

Mismagius @ Leftovers
Levitate
Timid
-Shadow Ball
-Thunderbolt
-Substitue
-Nasty Plot
Sub and spam nasty plot, then sweep like crazy. Leftovers helps heal the damage from sub. Not too sure about this one though, because sub is usually always one-shotted. I'm thinking about replaceing it or Gengar with Espeon.
So that's my team, I know teams with that many same types is risky, but I'm a little ocd and have to have a themed team. If I'd have to replace anything, I'm hoping to keep it within the theme. Any suggestions would be great.
Also, I've been thinking about a possible moveset for Umbreon that I need an opinion on. Here it is:
Umbreon @ Leftovers
Synchronize
Bold
-Mean Look
-Yawn
-Dream Eater
-Confuse Ray/Baton Pass
Trap them with mean look, yawn, then spam dream eater. If they wake up, yawn again since they're trapped, and repeat, being healed at the same time. Maybe Confuse Ray to help with yawn taking two turns, or baton pass to switch in a counter after they're asleep. Thoughts?