Kay
Fire 
Front row 
Knight Tier 1 Immortality
Effect 1: Apply Buff
Activation Condition: At the Brink of Death
Target: Self
Damage Immunity: Become immune to damage.
Effect 2: Immortality
Activation Condition: At the Brink of Death
Target: Self
Prevents death when receiving fatal damage.
Charge
Effect 1: Apply Buff
Target: Self
Melee Attack +88%.
Effect 2: Apply Buff
Target: Self
Ignore Damage Reduction +15%.
Determination
Kay's Critical Hit Rate and Critical Damage are increased (up to 2 stacks). While the Ultimate is active, initiating a basic attack reduces the cooldown of Active Skill - Determination by 3s.
Target: Self
Effect: Apply Buff
Attribute Stack: Per stack
Critical Hit Chance +24%, Critical Damage +48% (Max 2 stacks).
Inferno Awakening
Effect: Apply Buff
Target: Self
Change Appearance: Transform into a figure specialized for battles.
Effect: At the end of the effect: Activate Active Skill - Burn to Ashes.
Burn To Ashes - Active Skill
Inflict damage equal to 1920% of Attack.
Target: All Enemies
Character sizes
Recommended stats
About Ignore Damage Reduction %
This stat only works if the boss has passive skills giving him damage reduction. If not, it's useless.
Avalon, Reincarnation of Stars and Raids usually all have this passive, but always double check to make sure.
Recommended cards
Cards will always change depending on the stage and content you are currently facing, this is just a couple of examples on what cards work for this character.
Permeating Sensuality (Anessa)
Melee Attack Damage +60%
Melee Critical Strike Chance +10%
Charm (Lilith)
Status Effect Accuracy +25%
Holy Sword's Blessing (Ethan)
HP +40%
Prydwen (Percival)
HP +60%