Rillaboom is pretty good in RU and doubles UU. In most other popular formats, there are no good reasons to use Rillaboom when you can use a better Pokemon like Venusaur, Roserade, or Tsareena.
Moveset for RU:
Rillaboom @ choice scarf
Ability: overgrow
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly nature
- U-turn
- wood hammer
- knock off
- earthquake
Moveset for doubles UU:
Rillaboom @ assault vest
Ability: overgrow
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly nature
- fake out
- wood hammer
- knock off
- high horsepower
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