Gen 9 OU
Chi-Yu @ Heavy-Duty Boots / Choice Specs / Choice Scarf
Ability: Beads of Ruin
Tera Type: Ghost
EVs: 4 Def / 252 SpA / 252 Spe
Timid Nature
- Lava Plume
- Hex
- Overheat
- Dark Pulse
This is an interesting set I made which aims to burn Chi-Yu's checks like Tyranitar, Hariyama, and Ting-Lu, while maintaining its ability to beat Ceruledge and Baxcalibur. STAB Lava Plume is very strong and makes it risky for anything to reliably switch into Chi-Yu without getting burned. Hex allows Chi-Yu to hit Hariyama hard when it's burned, Overheat and Dark Pulse are your average Chi-yu nukes. Ghost is a mainly defensive Tera type that gives Chi-Yu an immunity to things like Mach Punch from Breloom and Pawmot, and Extreme Speed from Dragonite, which will try to revenge-kill you. It also makes you immune to Hariyama's Drain Punch, Dachsubun's Body Press and gives you neutrality to something like Ting-Lu's Earthquake or Tyranitar's Rock Blast. It also boosts the power of Hex which lets you at least do something to Dachsubun.
I'm not going to go too in depth with teammates as this set is borderline cheese, but Clodsire is a pretty nice partner for spreading Toxic and using Spikes. Pokemon that have shared checks with Chi-yu like Dragonite, Dragapult, Espathra, and Roaring Moon enjoy having Chi-yu cripple their checks and can later handily defeat them.