Set: Trick Room Reuniclus

Reuniclus @ Life Orb 

Ability: Magic Guard 

EVs: 192 HP / 64 Def / 252 SAtk 

Quiet Nature (+SAtk, -Spd) 

-Trick Room 

-Psychic 

-Focus Blast 

-Shadow Ball

Trick Room Reuniclus has been around for a while, but it's always been overshadowed by the standard Calm Mind variant. Although the CM set works best on bulkier teams for taking down defensive stall cores, TR Reuniclus is excellent for sweeping through more offensively-inclined teams. Its significantly lower usage also means it tends to be a lot less prepared for.

This set doesn't have the longevity of standard Reuniclus, so you'll only want to bring it out late-game or when you feel pretty confident in a sweep. Just bring it in on something it can set up on, like Conkeldurr, and begin cleaning through teams after a Trick Room. Since the majority of teams aren't stall-based, opponents can run into a lot of trouble with this set.

Reuniclus has everything in needs to work as an effective standalone TR sweeper. A Life Orb-boosted Psychic off of base 125 SAtk dishes out a lot of damage. Focus Blast is a good coverage move, particularly for hitting Steel-types and Tyranitar. Trick Room also means Reuniclus will outspeed and OHKO standard specially defensive Tyranitar, even with the Sandstorm boost. Shadow Ball is helpful for covering other Reuniclus, Latios and Latias, who would all wall the set otherwise.

TR Reuniclus has a couple of other good options. Psyshock 2HKOes Blissey after Stealth Rock, but it's a weaker move otherwise. HP Fire is also an interesting possibility in the last moveslot, as it'll net the surprise KO on Scizor. As far as teammates go, Conkeldurr is notable for taking on many Reuniclus switch-ins. The two also complement each other nicely. All in all, TR Reuniclus is a giant threat that can single-handedly sweep unprepared teams.