Hoopa / Hoopa-Unbound is a great Special sweeper with sky-high Sp. Atk and a great Sp. Def to compliment it. It's unique typing also has a great offensive potential. Its useful STABs in Psychic / Psyshock / Hyperspace Hole and Shadow Ball or Dark Pulse, enabling it to check top-tier threats (such as [email protected], Venusaur, Slowbro).
Unfortunately, Hoopa's typing comes with a cost. It is easy to Pursuit trap and is vulnerable to Knock Off, two of which are common moves. Hoopa-Unbound is also weak to Bug-types and Fairy-types, which can pose hinder its ability to perform its role successfully. Although its speed / typing is a big hinderance, Hoopa / Hoopa-Unbound still has the capability to break through walls under certain circumstances.
Here is a set for each form....
Role: Trick Room Sweeper
EVs: 200 HP / 252 Sp. Atk / 56 Sp. Def
Quiet Nature (+ Sp. Atk, - Speed)
- Trick Room
- Hyperspace Hole / Psychic / Psyshock
- Shadow Ball / Focus Blast
- Substitute / Shadow Ball
Hoopa doesn't necessarily have the speed to perform a fast sweep, while using Choice Scarf doesn't boost its speed by much and Hoopa is locked into that move (unless if you switch out).
One thing Hoopa is great at is setting up Trick Room. By doing so, it can outspeed threats with a higher speed stat (which Hoopa generally lures in) and easily land the OHKO with its powerful STABs and coverage options.
Hyperspace Hole is good for breaking through Substitutes and bypassing Protect. Psychic is a more powerful alternative, while Psyshock nails Sp. Def walls.
Shadow Ball is great STAB, while Focus Blast deals with Steel-types and Rock-types that can wall this set. Substitute is used only when Hoopa is facing against Sp. Atk sweepers or to take advantage of the switches that Hoopa forces.
Note: I didn't invest 0 IVs in Speed because, when Trick Room is over, it would (theoretically) have beaten the faster targets, leaving only the slower Pokemon left.
Role: Substitute + Nasty Plot Sweeper
EVs: 4 HP / 252 Atk / 252 Speed
Timid Nature (- Atk, + Speed)
- Nasty Plot
- Dark Pulse / Focus Blast
- Hyperspace Hole
Hoopa-Unbound has a usable speed stat and a sky-high Sp. Atk! This enables it to successfully pull of a Substitute + Nasty Plot sweep.
Dark Pulse gets good STAB, while Focus Blast has decent coverage against Steel-types that try to wall it.
Hyperspace Hole is used primarily to break through Subsitute / Protect, although Psychic can be used as a slightly more powerful alternative.
Although Hoopa can run a mixed set or even a physical set, Hoopa prefers to abuse its higher Sp. Atk. A Substitute + Calm Mind set can be run, but Hoopa generally doesn't have the bulk or speed to pull it off.
Hoopa-Unbound, unlike its Confined form, can run a physical set successfully. With options like Hyperspace Fury, Gunk Shot, and Focus Punch in its arsenal, it can break through tanks / walls. This set also prefers Substitute in order for it to set up Focus Punch.
Hoopa-Unbound can also run a Trick Room set with Hyper Space Fury / Brick Break / Gunk Shot, although Hoopa is more successful in performing a Trick Room set.
Note: Update is needed for the tier change.
Dark-types / Ghost-types Confined Hoopa is extremely vulnerable to dark and ghost-type moves, making it vulnerable to Knock Off and Shadow Ball spam.
Pursuit Trappers Hoopa's typing is once again its major flaw. Because of Pyschic / Ghost dual typing, many Pokemon, such as Tyranitar, Bisharp, and Scizor, are able to Pursuit trap Hoopa, which leaves it unable to switch out and completely vulnerable.
Sp. Def Walls / Tanks Sp. Def walls, such as Chansey, can wall Hoopa if it isn't carrying Focus Blast / Psyshock.
Faster Sweepers If Hoopa isn't played correctly and doesn't set up Trick Room, faster Ghost-type sweepers, such as Gengar, can OHKO Hoopa with its STABs. Slower Pokemon that also take advantage of Trick Room can also threaten Hoopa.
Bug-types Hoopa-Unbound faces similar problems, except it has a 4x weakness to Bug-types. This makes it vulnerable to U-turn and Bug-types in general (one such example is Scizor).
Fairy-types Hoopa-Unbound also has a 2x weakness to Fairy-types, which is especially bad because of the rise of Fairy-types. This means that Fairy-types, like Clefable, can pose a threat to Hoopa-Unbound.