
Beheeyem is a Psychic type Pokémon introduced in Gen V. He is a moderately bulky Psychic who is exceptionally slow however hits like a truck with 125 SpA.
Stats:
HP 75
Atk 75
Def 75
SpA 125
SpD 95
Spe 40
It's stats basically determine the EVs. SpA and HP are maximised and the only question left is whether Spe should be reduced to a minimum for a Trick Room set or left.
It's stats are a lesser echo of Reuniclus’ however it lacks Magic Guard which is one of Reuniclus’ defining features and instead is cursed with a choice between Synchronise and Telepathy. Synchronise is always preferred in singles as it has an effect that activates. It's DW ability is Analytic which combined with its sky high special attack and low speed will allow it to hit even harder with an additional 1.3X boost to its attacks.
It possesses enough attacking options to form a set though its STAB is not particularly useful in the current metagame hitting few Pokémon other than Sawk, Garbodor and Haunter SE.
Its supporting movepool contains Toxic, Thunder Wave, dual screens, and Trick Room.
Trick Room
Beheeyem @ Leftovers / Life Orb
Synchronise
252 HP / 252 SpA / 4 SpD
Quiet (+SpA, -Spe)
0 Spe IVs
-Trick Room
-Nasty Plot / Recover
-Psychic / Psyshock
-Thunderbolt / Energy Ball
The most common set encountered it often runs 3 attacks with Psychic/Thunderbolt/Energy Ball. Rarely runs Shadow Ball. Acts as a good counter to the birds if Trick Room is up as it can OHKO with Thunderbolt.
Nasty Plotter
Beheeyem @ Leftovers
Synchronise
252 HP / 252 SpA / 4 SpD
Modest (+SpA, -Atk)
-Nasty Plot / Calm Mind
-Recover
-Psychic / Psyshock
-Thunderbolt / HP Fighting / Energy Ball / Shadow Ball
Generally a bad idea. Rarely survives long enough to boost and lacks Reuniclus’ bulk that allows it to work in OU. Nasty Plot vs. Calm Mind is a power versus survivability choice. Charge Beam is an option for slower boosting but more damage while boosting. Calm Mind can run a Bold (+Def, -Atk) 252 HP / 252 Def / 4 SpD for more bulky but 75/75/95 defences will still be sweep by some of the heavy hitters in the tier.
Jolly Swellow still gets a 2HKO on the Bold variant with a Guts Facade doing 62.71%- 74.01%. Duosion is generally better because of Eviolite and Magic Guard.
(DW) All Out Attacker
Beheeyem @ Life Orb
Analytic
252 HP / 252 SpA / 4 SpD
Modest
-Psychic / Psyshock
-Energy Ball
-HP Fighting
-Thunderbolt
While unreleased and not particularly useful Beheeyem deals immense damage with a 1.69X boost from LO and Analytic. This hits harder than Mewtwo with a LO and Psychic. But you're slow as crap.
So discuss. Is Beheeyem a good Trick Roomer? Does its shallow move pool have enough depth for it to function in the current NU metagame? Can it differentiate itself from Duosion without Magic Guard?