If a level 100 Shuckle with Rollout met these conditions, you'd have a ridiculously powerful attack.
>- Both allies in a triple battle use Helping Hand
- Both allies have the Ability Flower Gift and the weather is sunny
- Shuckle holds a Metronome
- Shuckle has used Power Trick
- Shuckle has the Ability Pure Power as a result of Skill Swap
- It is the 5th turn of using a Defense Curl-boosted Rollout consecutively without any misses
- Rollout is a critical hit
- Shuckle has its maximum Defense stat (with IVs, EVs and Nature taken into account) and the target likewise has its minimum Defense stat
http://bulbapedia.bulbagarden.net/wiki/Shuckle#Trivia