Rillaboom @ Rillaboomite  
Ability: Grassy Surge  
Level: 50  
EVs: 252 HP / 252 Atk / 4 SpD  
Adamant Nature  
IVs: 0 SpA  
- Grassy Glide  
- Swords Dance  
- High Horsepower  
- Protect

Unown
Move options:
- offensive: Darkest Lariat, Knock Off, Drain Punch

Unown
Defensive calcs:
- 252+ Atk Glastrier Icicle Crash vs. 252 HP / 0 Def Mega Rillaboom: 162-192 (78.2 - 92.7%) -- guaranteed 2HKO after Grassy Terrain recovery
Offensive calcs:
- +2 252+ Atk Mega Rillaboom High Horsepower vs. 252 HP / 0 Def Torkoal: 184-218 (103.9 - 123.1%) -- guaranteed OHKO
- +1 252+ Atk Mega Rillaboom High Horsepower vs. 236 HP / 4 Def Incineroar: 198-234 (99 - 117%) -- 93.8% chance to OHKO
- 252+ Atk Mega Rillaboom Grassy Glide vs. 0 HP / 0 Def Urshifu-Rapid Strike in Grassy Terrain: 176-210 (100.5 - 120%) -- guaranteed OHKO
- 252+ Atk Mega Rillaboom Grassy Glide vs. 252 HP / 4 Def Mega Slowking in Grassy Terrain: 210-248 (103.9 - 122.7%) -- guaranteed OHKO

Unown
Useful partners:
- screen setter: Regieleki, Grimmsnarl
- redirection: Blastoise
- Grassy Glide abuser: Lurantis, Tsareena