Rammus accelerates in a ball, gaining up to 150-235% Movement Speed over 6 seconds. On enemy collision, he stops, dealing 100/130/160/190/220 (+100% bonus Ability Power) magic damage to nearby enemies, knocking them back, and slowing them by 40/50/60/70/80% for 1 second.
Can be reactivated to end the effect early and put Powerball on cooldown.
Powerball is a channeled spell and is subject to interruption by spells that prevent casting.
Casting Powerball cancels Defensive Ball Curl and puts it on cooldown.