The undisputed queen of Break support in Honkai: Star Rail. Ruan Mei supercharges every team she joins through her Overtone DMG amplifier, team-wide SPD boost, and a field that grants all allies All-Type RES PEN while extending Weakness Break, making her the best-in-slot support for virtually any hypercarry or Break-centric composition.
Deals Ice DMG equal to 50% of Ruan Mei's ATK to a single target enemy. Low priority in combat; spending Skill Points on her Skill is almost always the right play. Use Basic only when conserving SP for your damage dealers.
Ruan Mei gains Overtone, a 3-turn buff (decreasing by 1 at the start of her turn). While Overtone is active, all allies' DMG increases by 16% and their Weakness Break Efficiency increases by 50%. This is her primary SP-spending action; use it whenever Overtone has expired to maintain full uptime on the DMG buff.
Deploys a field lasting 2 turns (decreasing by 1 at the start of her turn). Inside the field, all allies gain All-Type RES PEN of 15% and their attacks apply Thanatoplum Rebloom to enemies hit. When enemies attempt to recover from Weakness Break, Thanatoplum Rebloom triggers, extending Break duration, delaying their action by an amount equal to 20% of Ruan Mei's Break Effect + 10%, and dealing Break DMG equal to 30% of her Ice Break DMG. Enemies cannot have Thanatoplum Rebloom re-applied until they fully recover from Break.
Passively increases SPD by 8% for the entire team, excluding Ruan Mei herself. When any ally breaks an enemy's Weakness, Ruan Mei deals bonus Break DMG to that enemy equal to 60% of her Ice Break DMG. This means every Weakness Break in the team triggers additional Ice Break DMG, a significant source of bonus output that scales with Break Effect.
After using the Technique, Ruan Mei gains Silken Serenade. At the start of the next battle, automatically triggers her Skill once without consuming Skill Points, giving her instant Overtone uptime from turn one. In Simulated Universe with Silken Serenade, the team always enters battle treating the attack as hitting an enemy Weakness, and can reduce all enemies' Toughness regardless of Weakness type. For every Blessing held (up to 20), Toughness-Reducing DMG of this attack increases by 100%.
Ruan Mei's buffs are universal: her SPD boost, DMG amplifier, and RES PEN apply to the entire team. She is best-in-slot in Break DMG teams but works in virtually any composition that benefits from universal damage amplification.