Arctic Assault does not have an area of affect while colliding with an enemy champion; however, if multiple champions are hit by the charge itself, you may deal damage to multiple enemies.
Flail of the Northern Winds
COST: 40 / 35 / 30 / 25 / 20 Mana
COOLDOWN: 11 / 10 / 9 / 8 / 7
Active: Sejuani's next basic attack deals bonus magic damage to the target and enemies near it equal to their maximum health. She then swings her flail, dealing magic damage each second to enemies within range for 4 seconds.
If this ability is reactivated, Sejuani immediately starts swinging her flail.
Bonus Magic damage: 4 / 6 / 8 / 10 / 12% (+ 3% per 100 AP)of target's maximum health
The Frost debuff itself is not a form of CC and hence cannot be cleansed by items or abilities that remove CC. Permafrost, however, is CC and can be removed.
Frost cannot be applied to any target affected by Permafrost until 3 seconds after the Permafrost debuff expires. Due to this, Permafrost is the only one of Sejuani's abilities that do not apply Frost.
COST: 100 Mana
COOLDOWN: 130 / 115 / 100
Active: Sejuani throws her frost-forged bola in a line. If the bola hits an enemy champion, it shatters, stunning the target and nearby enemies for a short duration. If the bola reaches its maximum range, it shatters and slows enemies by 90% instead for the same duration. All enemies in the shatter area take magic damage.