The damage type that Senna deals is mostly Physical Damage.
Senna's damage type breakdowns as follows:
When units die near Senna, their souls are periodically trapped by the Black Mist. Senna can attack these souls to free them, absorbing the Mist that held them in death and granting Senna 8 gold. Mist fuels her Relic Cannon's power with increased Attack Damage (0.75 attack damage per soul), Attack Range (20 per mist stacks), and 160% Critical Strike Chance. Attacks from Senna's Relic Cannon take longer to fire, deals bonus damage, and briefly grant her a portion of her target's Movement Speed.Minions and lesser monsters that Senna kills have a 8.333% chance to spawn a Mist Wraith
Senna shoots a bolt of piercing shadow through an ally or enemy. dealing 30/65/100/135/170 (+50% bonus Attack Damage) physical damage to enemis and slowing them by 15 (+6% per 100 ability power) (+10) for 1/1.25/1.5/1.75/2 seconds. Allied champions hit are healed for 40/55/70/85/100 (+30% bonus Attack Damage) (+40% bonus Ability Power) (+1.6 Lethality) health. Basic attacks reduce Piercing Darkness's cooldown by 1 seconds.
Senna sends forth the black mist, dealing 70/115/160/205/250 (+70% bonus Attack Damage) physical damage to the first enemy hit. After a 1 second delay the target and other nearby enemies are rooted for 1/1.25/1.5/1.75/2 seconds.
Senna dissolves into a cloud of mist for 6/6.5/7/7.5/8 seconds, becoming a wraith. Allied champions who enter the mist are Camouflaged and become wraiths when they leave. Wraiths gain 20% (+1% per 20 Ability Power) Movement Speed. They are unselectable and hide their identities as long as no enemy champions are nearby.
Senna fires a blast of light with global range. Enemy champions hit take 250/400/550 (+115% bonus Attack Damage (+70% bonus Ability Power) physical damage. Allied champions hit in a wider area receive a shield for 3 seconds that absorbs 100/150/200 (+40% bonus Ability Power) damage. The shield's power scales with the amount of mist Senna has collected (+1.5 per Mist collected).The beam now collects Mist Wraiths.
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