Castorice is a 5-star Quantum character in Honkai: Star Rail. She is aligned with the Path of Remembrance, known for her daring risk-reward playstyle. Unlike most DPS units who thrive on raw attack or speed, Castorice turns HP sacrifice into strength, summoning her memosprite companion, Netherwing, to unleash devastating Quantum damage. Her gameplay rewards precision, strong team synergy, and resource control — making her one of the most mechanically rich characters in Honkai: Star Rail.

This guide explores her best builds, relics, light cones, and ideal team compositions to help you master her high-stakes, high-impact combat style. If you are new to the game, check out our Beginner’s Guide to Honkai: Star Rail for a comprehensive introduction!

Understanding Castorice’s Playstyle

Castorice’s unique power comes from “Newbud,” a special resource she generates when she or her allies lose HP. Once enough Newbud has accumulated, she can summon Netherwing, a memosprite that fights alongside her for several turns. Netherwing’s attacks scale directly with Castorice’s HP and Crit DMG, so every sacrifice she makes contributes to greater damage potential.

Her skill drains HP from the team to generate Newbud, while her ultimate brings Netherwing into play, delivering multi-hit Quantum strikes to all enemies. Her talent amplifies both her and Netherwing’s power depending on total HP lost. This creates a rhythm of draining, healing, and detonating damage — a dynamic flow of self-harm and empowerment that sets Castorice apart.

Because of this loop, she performs best in teams that can stabilize her health while amplifying her scaling. Managing HP, rather than avoiding it, is what unlocks her true potential.

Trace and Eidolon Priorities

Upgrading Castorice’s traces strategically ensures her output scales smoothly. Her Talent and Ultimate traces should be the top priorities, as they directly govern Netherwing’s summoning power and duration. The Skill trace follows, enhancing her Newbud generation and team-wide synergy. The Basic Attack is largely filler and can remain at lower levels.

Her first two Eidolons greatly improve her combat flow. The first enhances her damage against weakened foes, making it easier to finish battles quickly. The second accelerates her action after Netherwing is summoned, improving her rotation consistency. These two are the most valuable upgrades, with later Eidolons providing incremental benefits that further refine her playstyle.

Best Light Cones

Castorice’s signature light cone is her ideal weapon, offering a substantial HP bonus and allowing her to ignore a portion of enemy defense when she or Netherwing loses HP. It also advances her action after Netherwing disappears, ensuring seamless transitions between summon cycles.

If unavailable, focus on cones that increase HP, Crit DMG, or trigger buffs when HP changes. Light cones that grant damage bonuses for active summons or that trigger when HP drops also align well with her kit. The key is maintaining the balance between offensive scaling and sustain, allowing her to deal consistent damage without overexposing her team to danger.

Relics, Ornaments, and Stat Priorities

Castorice’s stat priorities are different from most DPS characters. Her main goal is to maximize HP and Crit-based scaling rather than stacking speed or attack. The Poet of Mourning Collapse relic set is the best choice, granting her a Crit Rate bonus when she maintains lower speed — a natural fit given her deliberate, heavy-hitting playstyle.

For planar ornaments, the Bone Collection’s Serene Demesne set is exceptional, offering both HP and Crit DMG increases once she reaches a high HP threshold. If unavailable, other HP-boosting or Crit-based ornaments serve as fine placeholders.

When assigning main stats and substats, prioritize the following:

• Body: HP% or Crit DMG
• Feet: HP% (avoid Speed to retain set bonuses)
• Sphere: HP% or Quantum DMG%
• Link Rope: HP% or ATK%
• Substats: HP%, Crit DMG, Crit Rate (secondary)

This build transforms her health pool into raw firepower. With every increase in HP, both Castorice and Netherwing grow stronger, making durability itself a source of damage.

Team Compositions and Synergies

Castorice functions best in carefully balanced teams that can sustain her HP drain while amplifying her damage. Because her kit continuously reduces the team’s health, reliable healers and buffers are essential.

A well-rounded team composition might include Castorice as the main DPS, Remembrance Trailblazer as a support providing True DMG and turn control, Luocha or Huohuo as the healer, and Bronya or Pela as the buffer or debuffer. This setup ensures constant healing, action advancement, and damage amplification, all crucial for keeping Castorice in her rhythm.

She can also share a lineup with other offensive characters such as The Herta or Mydei, forming a hybrid damage core. In such setups, her HP-drain mechanic doubles as a team enabler, as allies benefit from shared debuffs and enemy vulnerabilities.

Combat Strategy and Rotation Tips

Mastering Castorice is about controlling the tempo of battle rather than rushing through actions. Each cycle starts with generating Newbud using her skill, then transitioning to summoning Netherwing with her ultimate. The key is maintaining Netherwing’s presence as long as possible and ensuring that each HP-draining action is followed by timely recovery.

To maintain her efficiency in combat, keep these tactical points in mind:

• Use her HP-draining skill only when healing or shields are available to follow up immediately.
• Summon Netherwing after buff windows — time it so that damage-boosting effects are active throughout its duration.
• Avoid unnecessary Speed rolls on relics; her slower pace ensures stronger Crit synergy and predictable rotations.
• When the team’s HP is stable, push her offensive cycle; when it drops too low, focus on recovery before triggering another drain.

Her gameplay rewards foresight. Every successful battle with Castorice feels like a dance between risk and control — striking hard while maintaining stability through precise timing.

Strengths and Weaknesses

• Strengths: Exceptional HP-scaling damage potential, powerful multi-hit Quantum attacks through Netherwing, strong synergy with healers and Remembrance supports, and excellent durability that allows her to survive her own HP-draining mechanics.
• Weaknesses: Highly dependent on consistent healing and support coordination, vulnerable to mismanaged rotations or overuse of HP-draining skills, limited by speed tuning requirements, and difficult to play effectively without precise timing and planning.

Castorice embodies the principle of “power at a price.” Every action she takes demands foresight, and every ounce of strength comes from how well you manage her HP and sustain loop. Built correctly, she is one of the most formidable Quantum damage dealers in the game, capable of both immense burst and long-term pressure through Netherwing’s attacks.

Her complexity and reliance on timing make her less accessible for beginners, but those who invest the time to understand her flow will discover a uniquely dynamic character with unmatched potential. In the right hands, Castorice is not just strong — she’s unstoppable. For the best gaming experience, play Honkai: Star Rail on BlueStacks!