Cappa Juice

Scales with Ability Power (AP). Champions and effects flagged as AP-scaling get bigger damage, healing, or shield values when the holder stacks AP from items like Jeweled Gauntlet, Rabadon's Deathcap, and Nashor's Tooth, or from trait bonuses.

Effect fires when a unit secures a kill or assist. In Set 17, Kai'Sa's passive "On takedown, gain 10 mana" is a clean example, and Seeker's Armguard stacks +20 Armor / MR / AP per takedown.

Effect fires when the unit itself is killed, commonly on items that bank value during combat (see damage-storage) and discharge it as a final payload. The Annihilator is the Set 17 example: it stores 20% of damage dealt and unleashes it as true damage on death.

The carrier gains a permanent stack on each takedown (kill or assist) and keeps those stacks across rounds, unlike in-combat stacking which resets. Set 17 Ezreal is the headline example: every 8 takedowns earns him a permanent damage drone, so early-round farming compounds into late-game burst.