Spell vamp is a defensive stat which converts a percentage of the damage from either champion abilities or item actives into health. It only works for active champion abilities that do not modify basic attacks or apply on-hit effects (including true damage abilities). The exception to this rule is File:Center of the Universe.png Center of the Universe, which does proc all spell effects including spell vamp. The heal is calculated from damage after being reduced by enemy defense, such as magic resistance, armor or champion damage reduction.