Specs Maw (Eternatus) @ Choice Specs  
Ability: Dragon's Maw  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid / Modest Nature  
IVs: 0 Atk  
- Dragon Energy  
- Sludge Wave  
- Blue Flare / Volt Switch
- Final Gambit / Lunar Dance / Trick

Critical Hit (Eternatus) @ Scope Lens  
Ability: Sniper  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid / Modest Nature  
IVs: 0 Atk  
- Focus Energy  
- Draco Meteor  
- Sludge Wave  
- Overheat

SimplePlot (Eternatus) @ Black Sludge  
Ability: Simple  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Nasty Plot  
- Core Enforcer  
- Sludge Wave / Sludge Bomb
- Earth Power

MoldyPlot (Eternatus) @ Black Sludge  
Ability: Mold Breaker  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Nasty Plot  
- Core Enforcer  
- Sludge Wave / Sludge Bomb
- Blue Flare

Adaptability (Eternatus) @ Black Sludge  
Ability: Adaptability  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Core Enforcer  
- Sludge Bomb / Sludge Wave
- Blue Flare  
- Taunt

Regenerator (Eternatus) @ Life Orb / Choice Specs / Assault Vest
Ability: Regenerator  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Draco Meteor / Core Enforcer 
- Sludge Bomb
- Volt Switch  
- Blue Flare / Final Gambit / Spikes