Kayn Runes

The top Kayn runes in LoL patch 25.21 are Dark Harvest, Sudden Impact, Grisly Mementos, Relentless Hunter for Kayn's primary runes. Kayn's runes in his secondary tree best utilizes Cash Back and Cosmic Insight. These Kayn rune choices provide the best Kayn rune build for ranked.

• 

  

  The Darkin Scythe

  Kayn wields an ancient weapon and fights Rhaast, the darkin within it, for control. Either the Darkin will triumph, or Kayn will master Rhaast and become the Shadow Assassin.
  
  Darkin: Heal for a percentage of spell damage dealt to champions.
  
  Shadow Assassin: For the first few seconds in combat with enemy champions, deal bonus damage.

• 

  

  Reaping Slash

  Kayn dashes, then slashes. Both deal damage.

  Cost:

  • 40

  Cooldown:

  • 7/
  • 7/
  • 6/
  • 6/
  • 5

  Range:

  • 350
• 

  

  Blade's Reach

  Kayn damages and slows targets in a line.

  Cost:

  • 40/
  • 45/
  • 50/
  • 55/
  • 60

  Cooldown:

  • 13/
  • 12/
  • 11/
  • 10/
  • 9

  Range:

  • 700
• 

  

  Shadow Step

  Kayn can walk through terrain.

  Cost:

  • 90

  Cooldown:

  • 21/
  • 19/
  • 17/
  • 15/
  • 13

  Range:

  • 400
• 

  

  Umbral Trespass

  Kayn hides in an enemy's body, dealing massive damage when he bursts out.

  Cost:

  • 100

  Cooldown:

  • 120/
  • 100/
  • 80

  Range:

  • 550