Hatterene

Wielding the highest Special Attack of any Pokemon to get Expanding Force and Speed lower than even Amoonguss, Hatterene is the poster child for Trick Room variants of Psychic-type spam teams. It deals with many of the usual Trick Room answers, including Iron Hands and Amoonguss, even being immune to the latter's Spore due to Magic Bounce. Magic Bounce also prevents potential Taunt users from shutting down Trick Room.

Hatterene requires two things to succeed; Trick Room and Psychic Terrain. Indeedee-F provides both with Psychic Surge, Trick Room, and Follow Me to help Hatterene set up its own Trick Room. It is nearly impossible to deny Trick Room against a lead of Hatterene and Indeedee-F. Torkoal and Ursaluna deal with Steel-types that resist both of Hatterene's STAB moves, and they also benefit from Trick Room.

Aforementioned Steel-types like Gholdengo are tougher to break through for Hatterene, as well as Dark-types that take neutral damage from Dazzling Gleam, such as Incineroar, Kingambit, and Chi-Yu, the latter of which has Snarl to lower Hatterene's damage output. Assault Vest Raging Bolt running Snarl also slows Hatterene down, despite being weak to Dazzling Gleam. Rillaboom changing the terrain, weakening Expanding Force greatly, and allowing priority moves to go through can also be a huge blow to a gameplan involving Hatterene.

Lastly, like most Trick Room sweepers, Hatterene is susceptible to Trick Room either being denied or fully stalled out, leaving it defenseless.