Ferrothorn @ Leftovers  
Ability: Iron Barbs  
Level: 50  
EVs: 252 HP / 172 Def / 84 SpD  
Relaxed Nature  
IVs: 0 Atk / 0 SpA / 0 Spe  
- Body Press  
- Iron Defense  
- Leech Seed  
- Protect

Unown
Options:
- offensive: Power Whip, Gyro Ball
- supportive: Thunder Wave
- items: Figy Berry, Sitrus Berry

Unown
Offensive calcs:
- +2 172+ Def Ferrothorn Body Press vs. 236 HP / 4 Def Incineroar: 206-244 (103 - 122%) -- guaranteed OHKO
- +2 172+ Def Ferrothorn Body Press vs. 0 HP / 0 Def Mega Empoleon: 186-220 (116.9 - 138.3%) -- guaranteed OHKO
- +2 172+ Def Ferrothorn Body Press vs. 0 HP / 0 Def Mega Walrein: 208-246 (112.4 - 132.9%) -- guaranteed OHKO
- +2 172+ Def Ferrothorn Body Press vs. 68 HP / 4 Def Kartana: 152-180 (106.2 - 125.8%) -- guaranteed OHKO
Defensive calcs:
- 252 SpA Zapdos Hurricane vs. 252 HP / 84 SpD Ferrothorn: 76-90 (41.9 - 49.7%) -- guaranteed 3HKO after Leftovers recovery
- 252 Atk Mega Falinks-Combat Close Combat vs. 252 HP / 172+ Def Ferrothorn: 152-180 (83.9 - 99.4%) -- guaranteed 2HKO after Leftovers recovery
- 4 Atk Kartana Sacred Sword vs. 252 HP / 172+ Def Ferrothorn: 74-88 (40.8 - 48.6%) -- guaranteed 3HKO after Leftovers recovery

Unown
Useful partners:
- Rain setter: Pelipper, Politoed, Mega Walrein
- others: Urshifu-Rapid Strike, Tapu Fini