Verified for patch 16.8.1

Statikk Shiv

Every 3rd attack deals 30 + 50% of the holder's Ability Power as additional magic damage to 4 enemies.

Source

Artifact

Effects

AP: 15
APScalar: 0.5
AS: 50
Damage: 30
NumTargets: 4

Statikk Shiv scales with

Ability Power On the Menu

Scales with Ability Power. Damage and effect magnitudes that read "(scales with AP)" target this mechanic.