[Foolproof Plan] Seiun Sky

SSR Stamina

Analysis

Tier A. The second-best Stamina SSR in the game, with absurd mood support and a front-runner kit that lands her right behind Super Creek.

Seiun Sky is an endurance card built for long-distance front-runners, and her real selling point is mood. Mood Effect reaches 40% at Lv45, and her Lv30 unique tacks on another +15. Every mood swing you trigger turns into noticeably more stat gain over a Career. Stack a 35% Friendship Bonus at Lv50 on top and your rainbow stamina sessions actually scale instead of fizzling. The sneaky-good stat is Specialty Priority: 65 at Lv50, plus +20 from the unique. She camps the stamina tile relentlessly, even in a deck that wasn’t built around her.

Her skills go all-in on escape tactics. Hints cover Long Shot, Trick (Front), and the escape-acceleration line. Events hand you Second Wind, Escape Artist (Lv3 hint on the good roll), and Fast-Paced, with Dodging Danger and Keeping the Lead filling out the rest. Strong value for a runaway build.

The problem is Super Creek. She does the same job with more raw stamina output and a better recovery package, so most decks slot Creek first. Seiun Sky’s flat gains are also weak. A +1 Stamina Bonus means she’s carried entirely by mood and friendship.

Pros: 40% +15 mood, 35% friendship, monster specialty priority, deep front-runner skill pool
Cons: only +1 Stamina Bonus, lives in Super Creek’s shadow, kit only shines for escape strats

Pull her if you’re short on stamina cards or you main runaways. Already running Creek? She’s optional.

Card details

Field	Value
Character	Seiun Sky
Rarity	SSR
Type	Stamina
Obtain	Gacha
Global release	Jun 26, 2025
Hint skills	Inner Post Proficiency ○, Long Shot ○, Trick (Front), Frenzied Late Surgers, Hesitant Pace Chasers, Tail Held High
Event skills	Dodging Danger, Second Wind, Fast-Paced, Escape Artist, Keeping the Lead

Support effects

Effect	What it does	Values
Friendship Bonus	Increases the effectiveness of Friendship Training	Lv1: 10%, Lv30: 25%, Lv50: 35%
Mood Effect	Amplifies the effect of mood when training together	Lv10: 10%, Lv25: 30%, Lv45: 40%
Stamina Bonus	Increases Stamina gain when training together	Lv35: 1
Initial Friendship Gauge	Increases initial Friendship Gauge when beginning a Career playthrough	Lv10: 10, Lv25: 20, Lv45: 25
Race Bonus	Increases stat gain from races	Lv10: 1%, Lv25: 5%
Fan Bonus	Increases fan gain from races	Lv10: 1%, Lv25: 10%, Lv45: 15%
Hint Levels	Increases the level of hints gained through events	Lv45: 2, Lv50: 3
Hint Frequency	Increases the frequency at which hint events occur	Lv45: 30%, Lv50: 40%
Specialty Priority	Increases the frequency at which the character participates in their preferred training type	Lv1: 5, Lv30: 50, Lv50: 65

Unique effect

Unlocks at Lv 30. Mood Effect: +15, Specialty Priority: +20

Training events

Be Strategic ☆

Option 1: Wit +5, Energy +10, Mood +1, Bond +5, Skill Dodging Danger (hint Lv1)
Option 2: Skill points +30, Bond -5, Skill Second Wind (hint Lv1)

Beware of the Trap

Option 1: Speed +15, Stamina +15

It’s All to Win

Option 1: random — Speed +10, Stamina +10, Wit +10, Skill points +30, Mood +1, Skill Escape Artist (hint Lv3) / Speed +5, Stamina +5, Wit +5, Energy +10, Skill points +5, Mood +1, Skill Fast-Paced (hint Lv1)

Be Strategic ☆

Option 1: Wit +5, Energy +10, Mood +1, Bond +5, Skill Dodging Danger (hint Lv1)
Option 2: Skill points +30, Bond -5, Skill Second Wind (hint Lv1)

Beware of the Trap

Option 1: Speed +15, Stamina +15

It’s All to Win

Option 1: random — Speed +5, Stamina +5, Wit +5, Energy +10, Skill points +5, Mood +1, Skill Fast-Paced (hint Lv1) / Speed +10, Stamina +10, Wit +10, Energy +10, Skill points +30, Mood +1, Skill Escape Artist (hint Lv3)