Check:
Curiosity (Moltres-Galar) @ Whatever you want really
Level: 100
Modest Nature
Tera Type: Fire
Ability: Berserk
EVs: 252 SpA / 4 SpD / 252 Spe
- Fiery Wrath
- Tera Blast
- Agility
- Nasty Plot
Curiosity does indeed kill the cat.
This thing is practically irresistible to any Meowscarada. It sees the kill with triple axel and goes for it, not knowing that's its falling right into a deadly trap.
252 Atk Choice Band Protean Meowscarada Triple Axel (40 BP) (3 hits) vs. 0 HP / 0 Def Moltres-Galar: 576-684 (179.4 - 213%) -- guaranteed OHKO
Unfortunately, this is precisely when it terastalises to fire and kills it in one fell swoop.
252 Atk Choice Band Protean Meowscarada Triple Axel (40 BP) (3 hits) vs. 0 HP / 0 Def Tera Fire Moltres-Galar: 144-171 (44.8 - 53.2%) -- approx. 26.6% chance to 2HKO
252+ SpA Tera Fire Moltres-Galar Tera Blast (80 BP) vs. 0 HP / 4 SpD Meowscarada: 320-378 (109.2 - 129%) -- guaranteed OHKO
You could also tera turn one and agility and kill with tera blast on turn 2, but that could end with them switching out Meowscarada, foiling your surprise.
The best part is that its applications don't even end here. Tera Blast Fire also has some great applications to surprise a bunch of steel types that normally wall it.
252+ SpA Tera Fire Moltres-Galar Tera Blast (80 BP) vs. 252 HP / 0 SpD Corviknight: 272-324 (68 - 81%) -- guaranteed 2HKO after Leftovers recovery
252+ SpA Tera Fire Moltres-Galar Tera Blast (80 BP) vs. 0 HP / 0 SpD Kingambit: 272-324 (79.7 - 95%) -- 50% chance to OHKO after 1 layer of Spikes
252+ SpA Tera Fire Moltres-Galar Tera Blast (80 BP) vs. 252 HP / 0 SpD Skarmory: 320-380 (95.8 - 113.7%) -- 75% chance to OHKO
252+ SpA Tera Fire Moltres-Galar Tera Blast (80 BP) vs. 0 HP / 4 SpD Iron Treads: 320-378 (99.6 - 117.7%) -- 93.8% chance to OHKO
It still functions a lot like regular double dance Moltres, but with a fun little niche to surprise opponents.
Counter:
John Cena (Iron Hands) @ Sitrus Berry/Choice Band*
Level: 100
Adamant Nature
Tera Type: Electric
Ability: Quark Drive
EVs: 56 HP / 200 Atk / 252 Def
- Wild Charge
- Ice Punch/Swords Dance
- Close Combat
- Earthquake
This cat may be a magician, but it will never see John Cena coming.
On switch in, the worst hit it can possibly take is protean ice Triple axel. It survives and goes into sitrus berry range, healing up. If it doesn't get the highest roll, it survives the next triple axel even if it is a high roll.
252 Atk Choice Band Meowscarada Triple Axel (40 BP) (3 hits) vs. 56 HP / 252 Def Iron Hands: 198-234 (42.7 - 50.5%) -- approx. 0.4% chance to 2HKO
252 Atk Choice Band Meowscarada Flower Trick vs. 56 HP / 252 Def Iron Hands on a critical hit: 172-204 (37.1 - 44%) -- guaranteed 3HKO
Then it OHKOs with a Close Combat even if it is grass type.
200+ Atk Iron Hands Close Combat vs. 0 HP / 0 Def Meowscarada: 295-348 (100.6 - 118.7%) -- guaranteed OHKO
Pretty simple but still brutally effective at switching in and killing Meowscarada. *If you are not afraid of the double high roll triple axel kill (1/256 odds), you can swap out sitrus berry for another item, but sitrus berry locks in the victory, even living through most crit scenarios.