Blue Archive · student

Koyuki

Koyukiコユキ코유키

★★★✦Mystic HeavyArmor ⚔DamageDealer Striker Millennium Back MG Standard

Unchanged since July 18, 2026

LV.90

Combat

UrbanSOutdoorDIndoorB

Stats · Lv.90 Stats at any level →

HP18,930

ATK3,850

DEF418

Heal4,824

Crit209

Crit DMG200%

Crit RES100

Stability1,332

Accuracy104

Evasion190

Range750

DEF Pen0

CC Power100

CC RES100

Ammo25

Ammo cost5

Move Speed200

Heal Effectiveness10,000

Skills

Unexpected VariableEX Skill · Cost 4 · Lv.5

Deals damage by throwing 1 bomb arbitrarily at enemies in a circular area. Bullet: Deals 444% of ATK as damage. Electric Field: Deals 421% of ATK as damage. Flame: Deals 398% of ATK as damage.

Drag to see per-level scaling

One? Or Two?!+Basic Skill · Lv.10

Deals 463% of ATK as damage to 1 target, and up to 3 nearby enemies, every 30 sec. Reloads instantly. After defeating 6 enemies with Basic Skill, decreases its own EX Skill Cost by 3 (up to 1 time).

Drag to see per-level scaling

Do You Believe in Miracles?+Enhanced Skill · Lv.10

Increases ATK by 792. Also increases ATK by 26.6%.

Drag to see per-level scaling

Butterfly EffectSub Skill · Lv.10

Increases ATK when using an EX Skill, based on the type of bomb used (for 40 sec). Bullet: Increases ATK by 29.1%. Electric Field: Increases ATK by 27.5%. Flame: Increases ATK by 26%.

Drag to see per-level scaling

Loved gifts · raise this student's affinity the most

Board Game "The Life"SSRWorld's Most Useless GadgetSR

Liked gifts · genre favorites — extra affinity

Brain Teaser Puzzle CubeSR · matches 2 tags30-Color Paint SetSRAstronomical TelescopeSRCosplayer Coke-Bottle GlassesSRTeddy Bear with BowSR

Exclusive gear

Challenge CoinT1 · Bond 15 · ATK +500Challenge CoinT2 · Bond 20 · Basic skill upgrade

Star levels · credits and Eleph per star

2★

10,000 Credit Points + 30x Koyuki's Eleph

3★

40,000 Credit Points + 80x Koyuki's Eleph

4★

200,000 Credit Points + 100x Koyuki's Eleph

5★

1,000,000 Credit Points + 120x Koyuki's Eleph

Skill levels · per skill slot, per level

EX skill Lv.1 → 2

80,000 Credit Points + 12x Beginner Tactical Training Blu-ray (Millennium) + 12x Voynich Manuscript Page

Basic / Enhanced / Sub skill Lv.1 → 2

5,000 Credit Points + 5x Beginner Tech Notes (Millennium)

EX skill Lv.2 → 3

500,000 Credit Points + 12x Normal Tactical Training Blu-ray (Millennium) + 18x Beginner Tactical Training Blu-ray (Millennium) + 13x Damaged Voynich Manuscript + 31x Crystal Haniwa Fragment

Basic / Enhanced / Sub skill Lv.2 → 3

7,500 Credit Points + 8x Beginner Tech Notes (Millennium)

EX skill Lv.3 → 4

3,000,000 Credit Points + 12x Advanced Tactical Training Blu-ray (Millennium) + 18x Normal Tactical Training Blu-ray (Millennium) + 11x Annotated Voynich Manuscript + 24x Broken Crystal Haniwa

Basic / Enhanced / Sub skill Lv.3 → 4

60,000 Credit Points + 5x Normal Tech Notes (Millennium) + 12x Beginner Tech Notes (Millennium) + 4x Voynich Manuscript Page

EX skill Lv.4 → 5

10,000,000 Credit Points + 8x Superior Tactical Training Blu-ray (Millennium) + 18x Advanced Tactical Training Blu-ray (Millennium) + 6x Intact Voynich Manuscript + 20x Repaired Crystal Haniwa

Basic / Enhanced / Sub skill Lv.4 → 5

90,000 Credit Points + 8x Normal Tech Notes (Millennium) + 4x Damaged Voynich Manuscript + 14x Crystal Haniwa Fragment

Basic / Enhanced / Sub skill Lv.5 → 6

300,000 Credit Points + 5x Advanced Tech Notes (Millennium) + 12x Normal Tech Notes (Millennium) + 10x Damaged Voynich Manuscript + 18x Crystal Haniwa Fragment

Basic / Enhanced / Sub skill Lv.6 → 7

450,000 Credit Points + 8x Advanced Tech Notes (Millennium) + 3x Annotated Voynich Manuscript + 14x Broken Crystal Haniwa

Basic / Enhanced / Sub skill Lv.7 → 8

1,500,000 Credit Points + 8x Superior Tech Notes (Millennium) + 12x Advanced Tech Notes (Millennium) + 4x Intact Voynich Manuscript + 8x Repaired Crystal Haniwa

Basic / Enhanced / Sub skill Lv.8 → 9

2,400,000 Credit Points + 12x Superior Tech Notes (Millennium) + 8x Intact Voynich Manuscript + 14x Repaired Crystal Haniwa

Basic / Enhanced / Sub skill Lv.9 → 10

4,000,000 Credit Points + 1x Secret Tech Notes

Weapon stars · cost per unique-weapon star

Unique weapon 2★

1,000,000 Credit Points + 120x Koyuki's Eleph

Unique weapon 3★

1,500,000 Credit Points + 180x Koyuki's Eleph

Unique weapon 4★

2,000,000 Credit Points + 200x Koyuki's Eleph

Unique weapon 5★

2,500,000 Credit Points + 1x Koyuki's Eleph

Gear tiers · cost per tier

Gear T1

500,000 Credit Points + 4x World's Most Useless Gadget + 80x Voynich Manuscript Page + 25x Damaged Voynich Manuscript

Unique Weapon

Mulli-GunATK +971 · HP +3416

A machine gun that's been through the wringer alongside Koyuki. Once, it was entirely submerged in seawater. During the repair process, its color changed. Other than that, it's still as sturdy as Koyuki, who never worries about such trivialities.

Transcendence · per-star stat bonuses

★★ATK +10.0% HP +5.0% Heal +7.5%★★★ATK +22.0% HP +12.0% Heal +17.5%★★★★ATK +36.0% HP +21.0% Heal +29.5%★★★★★ATK +53.0% HP +35.0% Heal +44.5%

Bond bonuses · max affinity

DEF+227HP+1005

Equipment slots

GlovesHairpinWatch

Profile

Full nameKurosaki Koyuki

Age15 years old

BirthdayFebruary 14th

Height4'11"

School year1st Year

IllustratorMISOM150

Voice actor乾夏寧

HobbyTesting her luck, escaping

MottoIt's my fault?!

A brilliant yet troublesome member of Millennium's Seminar. She's completely unaware of her unrivaled talent for mathematical decryption. She always sets out to test her luck. Even if she goes too far and lands in hot water, she never stops.