A Star That Lights the Night guide

A Star That Lights the Night

Erudition Light Cone for a wearer who regularly uses Assist Skill and can build up Sail; consider it when those actions make its layered damage bonuses useful.

Introduced in v4.4

A Star That Lights the Night gives its wearer passive DEF ignore, then rewards Assist Skill use with Energy and temporary Sail stacks. It suits a damage-focused wearer whose Assist Skill recurs often enough to maintain stacks and who can reach the threshold for its additional Ultimate bonus.

PathEruditionRarity5

A Star That Lights the Night GUIDE

Understand A Star That Lights the Night

Useful when…

Consider it for an Erudition wearer who uses Assist Skill repeatedly and benefits from both Assist Skill and Ultimate damage.
Its DEF ignore applies whenever the wearer deals damage, so it also supports damage outside those two named modes.

What does it do, and how does Sail work?

The wearer ignores 6% of a target’s DEF when dealing damage at S1. Each time the wearer uses Assist Skill, they regenerate 6 Energy and gain Sail for 2 turns, up to 3 stacks. At S1, each Sail stack increases Assist Skill damage by 20%. When Sail reaches 3 stacks, each stack also increases Ultimate damage by 32%. Sail therefore builds toward a distinct Ultimate benefit; the Assist Skill bonus applies per stack before that threshold is reached. The effect text does not specify how the 2-turn duration is refreshed, so do not assume an exact refresh or stack-expiration sequence beyond the stated duration and cap.

When is it useful?

Its value is conditional on the wearer actually using Assist Skill: that action supplies both the Energy and Sail needed to scale the named damage bonuses. A wearer who rarely uses Assist Skill will mostly receive the always-on DEF ignore, while a frequent user can build stacks for stronger Assist Skill damage and, at 3 stacks, the added Ultimate damage. The comparison options emphasize different mechanics: A Dream Scented in Wheat supplies CRIT Rate and Ultimate/Follow-Up ATK damage, After the Charmony Fall supplies Break Effect and post-Ultimate SPD, and An Instant Before A Gaze increases CRIT DMG and scales Ultimate damage with Max Energy up to 180 points at S1. They are alternatives only when their own damage profile matches the wearer; none duplicates Sail or its Assist Skill trigger.

What should be improved first?

Promotion raises the Light Cone through stages up to 6. Superimposition raises First Wish from S1 to S5 and consumes one S1 copy per step in the listed examples. At S5, DEF ignore reaches 10%, Energy per Assist Skill remains 6, the Sail cap remains 3, Assist Skill damage rises to 40% per stack, and the 3-stack Ultimate bonus reaches 48% per stack. Promotion is the direct investment in the Light Cone’s level progression; superimposition is a separate copy cost for improving its effect. Prioritize further superimposition when the wearer reliably triggers Assist Skill and will use both damage bonuses; otherwise the added effect may not justify consuming copies.

What can go wrong?

Do not treat the Ultimate bonus as active before Sail reaches 3 stacks, or count the Assist Skill trigger as a guaranteed full-stack setup. The 2-turn Sail duration makes regular Assist Skill use relevant, but the supplied effect does not explain turn timing or stack refresh details. Also avoid choosing this solely for Ultimate damage if the wearer cannot consistently trigger Assist Skill; An Instant Before A Gaze instead has an Ultimate-specific bonus tied to Max Energy, while A Dream Scented in Wheat has a stated Ultimate bonus plus Follow-Up ATK damage.

Limitations and tradeoffs

Its strongest named bonuses depend on repeated Assist Skill use and building to the Sail cap.
The extra Ultimate bonus begins only at 3 Sail stacks.
Raising superimposition consumes additional S1 copies.

Common mistakes to avoid

Counting the Ultimate bonus before Sail reaches 3 stacks.
Ignoring the Assist Skill condition when evaluating Energy and Sail generation.
Assuming Sail lasts longer than the stated 2 turns or that its refresh behavior is specified.

Effects and reference details

First Wish · Superimposition

The passive activates only on a wearer following Erudition. Each additional rank uses a duplicate or its designated special material.

S1 The wearer ignores 32% of the target's DEF when dealing DMG. When the wearer uses Assist Skill, they regenerate 6 Energy and gain "Sail," lasting for 2 turns and stacking up to 3 time(s). Each stack of "Sail" increases Assist Skill DMG by 20%. When "Sail" reaches 3 stacks, each stack of "Sail" increases Ultimate DMG by 20%.

S2 The wearer ignores 36% of the target's DEF when dealing DMG. When the wearer uses Assist Skill, they regenerate 6 Energy and gain "Sail," lasting for 2 turns and stacking up to 3 time(s). Each stack of "Sail" increases Assist Skill DMG by 25%. When "Sail" reaches 3 stacks, each stack of "Sail" increases Ultimate DMG by 25%.

S3 The wearer ignores 40% of the target's DEF when dealing DMG. When the wearer uses Assist Skill, they regenerate 6 Energy and gain "Sail," lasting for 2 turns and stacking up to 3 time(s). Each stack of "Sail" increases Assist Skill DMG by 30%. When "Sail" reaches 3 stacks, each stack of "Sail" increases Ultimate DMG by 30%.

S4 The wearer ignores 44% of the target's DEF when dealing DMG. When the wearer uses Assist Skill, they regenerate 6 Energy and gain "Sail," lasting for 2 turns and stacking up to 3 time(s). Each stack of "Sail" increases Assist Skill DMG by 35%. When "Sail" reaches 3 stacks, each stack of "Sail" increases Ultimate DMG by 35%.

S5 The wearer ignores 48% of the target's DEF when dealing DMG. When the wearer uses Assist Skill, they regenerate 6 Energy and gain "Sail," lasting for 2 turns and stacking up to 3 time(s). Each stack of "Sail" increases Assist Skill DMG by 40%. When "Sail" reaches 3 stacks, each stack of "Sail" increases Ultimate DMG by 40%.