
The Falling Snow
On auto attack, reduce Karsu's Max Mana by 1 (Min: 40).
After Stall (15), Snowpiercer arrows gain 33 (+33 per rank) Crit.
The Finisher
“I'm not here to talk.”
A range-5 Duelist whose Snowpiercer fires one more arrow per 50 Attack Speed (up to 14), spreading Frost. Raise Attack Speed. The Falling Snow cuts Max Mana down to 40 for more casts, The Frostbite adds extra arrows to auto attacks, and The Warband is a Backup that shares the stats it stacks with Duelists like Irini and Nyx.

Loose a volley of 5 (+1 per 50 Attack Speed) arrows at nearby enemies. Each arrow deals 25 (+100% Attack) (+100% Magic) damage and inflicts 3 (+2 per rank) Frost.
Max Arrows: 14
At B rank you pick one of three. Tap the cards to compare.

On auto attack, reduce Karsu's Max Mana by 1 (Min: 40).
After Stall (15), Snowpiercer arrows gain 33 (+33 per rank) Crit.

On cast, permanently gain 2 Crit, 3 Attack, and 4 Attack Speed.
At start of combat, other Duelists gain all stats gained from this ability. Backup.

Gains class Warrior
On auto attack, fire an additional arrow that inflicts 1 (+1 per 100 Attack Speed) Frost and deals 1 (+10% Attack)% of normal auto attack damage.
Specializations, upgrades and items players picked for Karsu in shared builds. Each shows the pick rate (bold), the clear rate of builds with that pick, and the number of builds.
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Picked from the game data to match Karsu's mechanics, class and the stats their abilities scale with. The tags before each item name say why.

+20 Attack Speed+25 Attack
If this item is held by a Duelist, double its stats.

+20 Attack Speed+15 Omnivamp
Every 15 auto attacks, if held by a Duelist this item gains 1 Attack Speed.

+200 Max HP+20 Attack Speed
If this item is held by a Duelist, double its stats.

+25 Starting Mana+4 Mana Regen+25 Magic
On cast, remove 30 Frost from each enemy with 30 or more Frost to Stun those enemies for 2.5 seconds.

+200 Max HP+30 Defense+20 Attack Speed
On auto attack, inflict 2 Frost on the target.
When auto attacked, inflict 2 Frost on the attacker.

+4 Mana Regen+25 Magic
On cast, inflict 12 Frost on the nearest enemy.
A and S rank upgrades are class upgrades: the options come from the hero's class, not the hero (game tutorial). In the current data the A and S rank options are the same list. S rank heroes also get one more item slot. Expand to see the options.

On auto attack, inflict 1 (+1 per 33 Attack Speed) Burn (Max: 10).

Whenever a Duelist attacks an enemy with Burn, they gain 2 Attack Speed. Backup.

On auto attack, inflict 1 (+1 per 50 Attack Speed) Poison (Max: 6).

Whenever a Duelist attacks an enemy with Poison, they gain 2 Attack Speed. Backup.

On auto attack, inflict 1 (+1 per 80 Attack Speed) Frost (Max: 6).

Whenever a Duelist attacks an enemy with Frost, they gain 2 Attack Speed. Backup.

On auto attack, gain 1 Crit and 1 Attack per Debuff on the target.

Duelists gain 1 Attack Speed per Rush trigger this game. Backup.

For Rush (10), gain +50% Crit.
After Stall (20), gain +50% Crit.

On Crit, heal (+50% Crit) health and gain 3 Mana.

Duelists gain 2 Attack Speed per reroll this game. Backup.

Every 9 auto attacks, gain 1 Shard.

Gain 1 Range and 40 Attack Speed.

At start of combat, if this Hero is adjacent to exactly one other Hero they both permanently gain 25 Attack Speed.

Duelists gain 1 Attack Speed per Stall trigger this game. Backup.
How to read the numbers: base value (+N% Stat) adds N% of that stat, (+A per B Stat) adds A for every B of that stat, and values split by slashes (/) are per rank.