diff --git a/internal/character/ruanmei/attack.go b/internal/character/ruanmei/attack.go
new file mode 100644
index 00000000..3548f13f
--- /dev/null
+++ b/internal/character/ruanmei/attack.go
@@ -0,0 +1,24 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/key"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+const Normal key.Attack = "ruanmei-normal"
+
+func (c *char) Attack(target key.TargetID, state info.ActionState) {
+	c.engine.Attack(info.Attack{
+		Key:        Normal,
+		Source:     c.id,
+		Targets:    []key.TargetID{target},
+		DamageType: model.DamageType_ICE,
+		AttackType: model.AttackType_NORMAL,
+		BaseDamage: info.DamageMap{
+			model.DamageFormula_BY_ATK: atk[c.info.AttackLevelIndex()],
+		},
+		StanceDamage: 30.0,
+		EnergyGain:   20.0,
+	})
+}
diff --git a/internal/character/ruanmei/data.go b/internal/character/ruanmei/data.go
new file mode 100644
index 00000000..ffbb88ae
--- /dev/null
+++ b/internal/character/ruanmei/data.go
@@ -0,0 +1,164 @@
+// Code generated by "charstat"; DO NOT EDIT.
+
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/prop"
+	"github.com/simimpact/srsim/pkg/engine/target/character"
+)
+
+var promotions = []character.PromotionData{
+	{
+		MaxLevel:   20,
+		ATKBase:    89.76,
+		ATKAdd:     4.488,
+		DEFBase:    66,
+		DEFAdd:     3.3,
+		HPBase:     147.84,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+	{
+		MaxLevel:   30,
+		ATKBase:    125.664,
+		ATKAdd:     4.488,
+		DEFBase:    92.4,
+		DEFAdd:     3.3,
+		HPBase:     206.976,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+	{
+		MaxLevel:   40,
+		ATKBase:    161.568,
+		ATKAdd:     4.488,
+		DEFBase:    118.8,
+		DEFAdd:     3.3,
+		HPBase:     266.112,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+	{
+		MaxLevel:   50,
+		ATKBase:    197.472,
+		ATKAdd:     4.488,
+		DEFBase:    145.2,
+		DEFAdd:     3.3,
+		HPBase:     325.248,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+	{
+		MaxLevel:   60,
+		ATKBase:    233.376,
+		ATKAdd:     4.488,
+		DEFBase:    171.6,
+		DEFAdd:     3.3,
+		HPBase:     384.384,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+	{
+		MaxLevel:   70,
+		ATKBase:    269.28,
+		ATKAdd:     4.488,
+		DEFBase:    198,
+		DEFAdd:     3.3,
+		HPBase:     443.52,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+	{
+		MaxLevel:   80,
+		ATKBase:    305.184,
+		ATKAdd:     4.488,
+		DEFBase:    224.4,
+		DEFAdd:     3.3,
+		HPBase:     502.656,
+		HPAdd:      7.392,
+		SPD:        104,
+		CritChance: 0.05,
+		CritDMG:    0.5,
+		Aggro:      100,
+	},
+}
+
+var traces = character.TraceMap{
+	"101": {
+		Ascension: 2,
+	},
+	"102": {
+		Ascension: 4,
+	},
+	"103": {
+		Ascension: 6,
+	},
+	"201": {
+		Stat: prop.BreakEffect,
+		Amount: 0.053,
+		Level: 1,
+	},
+	"202": {
+		Stat: prop.DEFPercent,
+		Amount: 0.05,
+		Ascension: 2,
+	},
+	"203": {
+		Stat: prop.BreakEffect,
+		Amount: 0.053,
+		Ascension: 3,
+	},
+	"204": {
+		Stat: prop.SPDFlat,
+		Amount: 2,
+		Ascension: 3,
+	},
+	"205": {
+		Stat: prop.BreakEffect,
+		Amount: 0.08,
+		Ascension: 4,
+	},
+	"206": {
+		Stat: prop.DEFPercent,
+		Amount: 0.075,
+		Ascension: 5,
+	},
+	"207": {
+		Stat: prop.BreakEffect,
+		Amount: 0.08,
+		Ascension: 5,
+	},
+	"208": {
+		Stat: prop.SPDFlat,
+		Amount: 3,
+		Ascension: 6,
+	},
+	"209": {
+		Stat: prop.DEFPercent,
+		Amount: 0.1,
+		Level: 75,
+	},
+	"210": {
+		Stat: prop.BreakEffect,
+		Amount: 0.107,
+		Level: 80,
+	},
+}
\ No newline at end of file
diff --git a/internal/character/ruanmei/eidolon.go b/internal/character/ruanmei/eidolon.go
new file mode 100644
index 00000000..d7852c36
--- /dev/null
+++ b/internal/character/ruanmei/eidolon.go
@@ -0,0 +1,64 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/event"
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/engine/modifier"
+	"github.com/simimpact/srsim/pkg/engine/prop"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+const (
+	E1         = "ruanmei-e1"
+	E2         = "ruanmei-e2"
+	E4         = "ruanmei-e4"
+	E4Listener = "ruanmei-e4-listener"
+)
+
+func init() {
+	modifier.Register(E1, modifier.Config{
+		Stacking: modifier.ReplaceBySource,
+		Listeners: modifier.Listeners{
+			OnBeforeHitAll: applyE1,
+		},
+	})
+	modifier.Register(E2, modifier.Config{
+		StatusType: model.StatusType_STATUS_BUFF,
+		Listeners: modifier.Listeners{
+			OnBeforeHitAll: applyE2,
+		},
+	})
+	// E4 is summarized to 1 buff mod
+	modifier.Register(E4, modifier.Config{
+		Stacking:   modifier.ReplaceBySource,
+		StatusType: model.StatusType_STATUS_BUFF,
+		CanDispel:  true,
+	})
+	// Causes known bug (?) of the breaking hit not benefitting from E4 as this should apply with OnBeforeBeingBreak
+	modifier.Register(E4Listener, modifier.Config{
+		Stacking:      modifier.ReplaceBySource,
+		BehaviorFlags: []model.BehaviorFlag{model.BehaviorFlag_REMOVE_WHEN_SOURCE_DEAD},
+		Listeners: modifier.Listeners{
+			OnBeforeBeingBreak: addE4,
+		},
+	})
+}
+
+func applyE1(mod *modifier.Instance, e event.HitStart) {
+	e.Hit.Defender.AddProperty(E1, prop.DEFPercent, -0.2)
+}
+
+func applyE2(mod *modifier.Instance, e event.HitStart) {
+	if mod.Engine().HasBehaviorFlag(e.Defender, model.BehaviorFlag_BREAK) {
+		e.Hit.Attacker.AddProperty(E2, prop.ATKPercent, 0.4)
+	}
+}
+
+func addE4(mod *modifier.Instance) {
+	mod.Engine().AddModifier(mod.Source(), info.Modifier{
+		Name:     E4,
+		Source:   mod.Source(),
+		Stats:    info.PropMap{prop.BreakEffect: 1},
+		Duration: 3,
+	})
+}
diff --git a/internal/character/ruanmei/ruanmei.go b/internal/character/ruanmei/ruanmei.go
new file mode 100644
index 00000000..8a146ebd
--- /dev/null
+++ b/internal/character/ruanmei/ruanmei.go
@@ -0,0 +1,57 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine"
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/engine/target/character"
+	"github.com/simimpact/srsim/pkg/key"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+func init() {
+	character.Register(key.RuanMei, character.Config{
+		Create:     NewInstance,
+		Rarity:     5,
+		Element:    model.DamageType_ICE,
+		Path:       model.Path_HARMONY,
+		MaxEnergy:  130,
+		Promotions: promotions,
+		Traces:     traces,
+		SkillInfo: character.SkillInfo{
+			Attack: character.Attack{
+				SPAdd:      1,
+				TargetType: model.TargetType_ENEMIES,
+			},
+			Skill: character.Skill{
+				SPNeed:     1,
+				TargetType: model.TargetType_SELF,
+			},
+			Ult: character.Ult{
+				TargetType: model.TargetType_ALLIES,
+			},
+			Technique: character.Technique{
+				TargetType: model.TargetType_SELF,
+				IsAttack:   false,
+			},
+		},
+	})
+}
+
+type char struct {
+	engine engine.Engine
+	id     key.TargetID
+	info   info.Character
+}
+
+func NewInstance(engine engine.Engine, id key.TargetID, charInfo info.Character) info.CharInstance {
+	c := &char{
+		engine: engine,
+		id:     id,
+		info:   charInfo,
+	}
+
+	c.initTalent()
+	c.initTraces()
+	c.initUlt()
+	return c
+}
diff --git a/internal/character/ruanmei/skill.go b/internal/character/ruanmei/skill.go
new file mode 100644
index 00000000..3159cc3d
--- /dev/null
+++ b/internal/character/ruanmei/skill.go
@@ -0,0 +1,76 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/engine/modifier"
+	"github.com/simimpact/srsim/pkg/engine/prop"
+	"github.com/simimpact/srsim/pkg/key"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+const (
+	SkillMain               = "ruanmei-skill"
+	OvertoneDmgBuff         = "ruanmei-skill-overtone-dmg-buff"
+	OvertoneBreakEfficiency = "ruanmei-skill-overtone-weakness-break-efficiency"
+)
+
+func init() {
+	modifier.Register(SkillMain, modifier.Config{
+		Stacking:   modifier.ReplaceBySource,
+		TickMoment: modifier.ModifierPhase1End,
+		Listeners: modifier.Listeners{
+			OnAdd:    addOvertone,
+			OnRemove: removeOvertone,
+		},
+	})
+	modifier.Register(OvertoneDmgBuff, modifier.Config{
+		Stacking:   modifier.ReplaceBySource,
+		StatusType: model.StatusType_STATUS_BUFF,
+	})
+	modifier.Register(OvertoneBreakEfficiency, modifier.Config{
+		Stacking:   modifier.ReplaceBySource,
+		StatusType: model.StatusType_STATUS_BUFF,
+	})
+}
+
+func (c *char) Skill(target key.TargetID, state info.ActionState) {
+	c.engine.AddModifier(c.id, info.Modifier{
+		Name:   SkillMain,
+		Source: c.id,
+	})
+}
+
+// Overtone is summarized from 4 "sub" mods with 2 being purely for display to only 2 "sub" mods
+func addOvertone(mod *modifier.Instance) {
+	// Calculate how much DMG Bonus should be given
+	rm, _ := mod.Engine().CharacterInfo(mod.Owner())
+	dmgAmt := skillDmg[rm.SkillLevelIndex()]
+	if rm.Traces["103"] {
+		dmgAmtA6 := 0.06 * float64(int((mod.OwnerStats().BreakEffect()-1.2)/0.1))
+		if dmgAmtA6 > 0.36 {
+			dmgAmtA6 = 0.36
+		}
+		dmgAmt += dmgAmtA6
+	}
+	for _, trg := range mod.Engine().Characters() {
+		mod.Engine().AddModifier(trg, info.Modifier{
+			Name:   OvertoneDmgBuff,
+			Source: mod.Owner(),
+			Stats:  info.PropMap{prop.AllDamagePercent: dmgAmt},
+		})
+		mod.Engine().AddModifier(trg, info.Modifier{
+			Name:   OvertoneBreakEfficiency,
+			Source: mod.Owner(),
+			Stats:  info.PropMap{prop.AllStanceDMGPercent: 0.5},
+		})
+	}
+}
+
+func removeOvertone(mod *modifier.Instance) {
+	for _, trg := range mod.Engine().Characters() {
+		mod.Engine().RemoveModifier(trg, OvertoneDmgBuff)
+		mod.Engine().RemoveModifier(trg, OvertoneBreakEfficiency)
+	}
+}
+
+// Technique doing Insert with autocast Skill (without consuming SP)
diff --git a/internal/character/ruanmei/stats.go b/internal/character/ruanmei/stats.go
new file mode 100644
index 00000000..520ac69a
--- /dev/null
+++ b/internal/character/ruanmei/stats.go
@@ -0,0 +1,100 @@
+package ruanmei
+
+var (
+	atk = []float64{
+		0.5,
+		0.6,
+		0.7,
+		0.8,
+		0.9,
+		1.0,
+		1.1,
+		1.2,
+		1.3,
+	}
+	skillDmg = []float64{
+		0.16,
+		0.176,
+		0.192,
+		0.208,
+		0.224,
+		0.24,
+		0.26,
+		0.28,
+		0.3,
+		0.32,
+		0.336,
+		0.352,
+		0.368,
+		0.384,
+		0.4,
+	}
+	ultResPen = []float64{
+		0.15,
+		0.16,
+		0.17,
+		0.18,
+		0.19,
+		0.2,
+		0.2125,
+		0.225,
+		0.2375,
+		0.25,
+		0.26,
+		0.27,
+		0.28,
+		0.29,
+		0.3,
+	}
+	ultBreakDamage = []float64{
+		0.3,
+		0.32,
+		0.34,
+		0.36,
+		0.38,
+		0.4,
+		0.425,
+		0.45,
+		0.475,
+		0.5,
+		0.52,
+		0.54,
+		0.56,
+		0.58,
+		0.6,
+	}
+	talentSpd = []float64{
+		0.08,
+		0.082,
+		0.084,
+		0.086,
+		0.088,
+		0.09,
+		0.0925,
+		0.095,
+		0.0975,
+		0.1,
+		0.102,
+		0.104,
+		0.106,
+		0.108,
+		0.11,
+	}
+	talentBreakDamage = []float64{
+		0.6,
+		0.66,
+		0.72,
+		0.78,
+		0.84,
+		0.9,
+		0.975,
+		1.05,
+		1.125,
+		1.2,
+		1.26,
+		1.32,
+		1.38,
+		1.44,
+		1.5,
+	}
+)
diff --git a/internal/character/ruanmei/talent.go b/internal/character/ruanmei/talent.go
new file mode 100644
index 00000000..d673ff8b
--- /dev/null
+++ b/internal/character/ruanmei/talent.go
@@ -0,0 +1,173 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/event"
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/engine/modifier"
+	"github.com/simimpact/srsim/pkg/engine/prop"
+	"github.com/simimpact/srsim/pkg/key"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+const (
+	Talent              = "ruanmei-talent"
+	TalentSpdBuff       = "ruanmei-talent-spd-buff"
+	TalentBreakListener = "ruanmei-talent-break-listener"
+	TalentBreak         = "ruanmei-talent-break-damage"
+)
+
+func init() {
+	modifier.Register(Talent, modifier.Config{
+		Listeners: modifier.Listeners{
+			OnAdd:         addSpdAndA2,
+			OnRemove:      removeUltResPen,
+			OnBeforeDying: removeTalentA2E2,
+		},
+	})
+	modifier.Register(TalentSpdBuff, modifier.Config{
+		Stacking:      modifier.Refresh,
+		StatusType:    model.StatusType_STATUS_BUFF,
+		BehaviorFlags: []model.BehaviorFlag{model.BehaviorFlag_STAT_SPEED_UP},
+	})
+	modifier.Register(TalentBreakListener, modifier.Config{
+		Stacking:      modifier.ReplaceBySource,
+		BehaviorFlags: []model.BehaviorFlag{model.BehaviorFlag_REMOVE_WHEN_SOURCE_DEAD},
+		Listeners: modifier.Listeners{
+			OnBeingBreak: doTalentBreakDamage,
+		},
+	})
+}
+
+func (c *char) initTalent() {
+	c.engine.AddModifier(c.id, info.Modifier{
+		Name:   Talent,
+		Source: c.id,
+	})
+
+	// Add mods to upcoming allies
+	// Slightly inaccurate as this should:
+	// - trigger after any entity gets created,
+	// - check if the target is part of allied team,
+	// - apply the relevant mods to the target.
+	c.engine.Events().CharactersAdded.Subscribe(
+		func(event event.CharactersAdded) {
+			for _, trg := range c.engine.Characters() {
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   TalentSpdBuff,
+					Source: c.id,
+					Stats:  info.PropMap{prop.SPDPercent: talentSpd[c.info.TalentLevelIndex()]},
+				})
+				if c.info.Traces["101"] {
+					c.engine.AddModifier(trg, info.Modifier{
+						Name:   A2,
+						Source: c.id,
+						Stats:  info.PropMap{prop.BreakEffect: 0.2},
+					})
+				}
+				if c.info.Eidolon >= 2 {
+					c.engine.AddModifier(trg, info.Modifier{
+						Name:   E2,
+						Source: c.id,
+					})
+				}
+			}
+		},
+	)
+
+	// Add mods to upcoming enemies (similar inaccuracy as above)
+	c.engine.Events().EnemiesAdded.Subscribe(
+		func(event event.EnemiesAdded) {
+			for _, trg := range c.engine.Enemies() {
+				if c.info.Eidolon >= 4 {
+					c.engine.AddModifier(trg, info.Modifier{
+						Name:   E4Listener,
+						Source: c.id,
+					})
+				}
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   TalentBreakListener,
+					Source: c.id,
+				})
+			}
+		},
+	)
+
+	// Add mods on BattleStart
+	c.engine.Events().BattleStart.Subscribe(func(event event.BattleStart) {
+		if c.info.Eidolon >= 2 {
+			for _, trg := range c.engine.Characters() {
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   E2,
+					Source: c.id,
+				})
+			}
+		}
+		if c.info.Eidolon >= 4 {
+			for _, trg := range c.engine.Enemies() {
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   E4Listener,
+					Source: c.id,
+				})
+			}
+		}
+		if c.info.Traces["103"] {
+			c.engine.AddModifier(c.id, info.Modifier{
+				Name:   A6,
+				Source: c.id,
+			})
+		}
+	})
+}
+
+// Add mods to existing allies
+func addSpdAndA2(mod *modifier.Instance) {
+	for _, trg := range mod.Engine().Characters() {
+		if trg != mod.Owner() {
+			mod.Engine().AddModifier(trg, info.Modifier{
+				Name:   TalentSpdBuff,
+				Source: mod.Owner(),
+				Stats:  info.PropMap{prop.SPDPercent: 0.1},
+			})
+		}
+		mod.Engine().AddModifier(trg, info.Modifier{
+			Name:   A2,
+			Source: mod.Owner(),
+			Stats:  info.PropMap{prop.BreakEffect: 0.2},
+		})
+	}
+}
+
+func removeUltResPen(mod *modifier.Instance) {
+	for _, trg := range mod.Engine().Characters() {
+		mod.Engine().RemoveModifier(trg, UltResPenAlly)
+	}
+}
+
+func removeTalentA2E2(mod *modifier.Instance) {
+	for _, trg := range mod.Engine().Characters() {
+		mod.Engine().RemoveModifier(trg, TalentSpdBuff)
+		mod.Engine().RemoveModifier(trg, A2)
+		mod.Engine().RemoveModifier(trg, E2)
+	}
+}
+
+// Applies Talent's Break Damage directly, without adding another mod
+func doTalentBreakDamage(mod *modifier.Instance) {
+	// Team member check skipped as it is deemed unnecessary
+
+	rm, _ := mod.Engine().CharacterInfo(mod.Source())
+	mult := talentBreakDamage[rm.TalentLevelIndex()]
+	if rm.Eidolon >= 6 {
+		mult += 2
+	}
+	maxStanceMult := ((mod.Engine().MaxStance(mod.Owner()) / 30) + 2) / 4
+	mod.Engine().Attack(info.Attack{
+		Key:          TalentBreak,
+		Targets:      []key.TargetID{mod.Owner()},
+		Source:       mod.Source(),
+		DamageType:   model.DamageType_ICE,
+		AttackType:   model.AttackType_ELEMENT_DAMAGE,
+		BaseDamage:   info.DamageMap{model.DamageFormula_BY_BREAK_DAMAGE: mult * maxStanceMult},
+		AsPureDamage: true,
+	})
+}
diff --git a/internal/character/ruanmei/technique.go b/internal/character/ruanmei/technique.go
new file mode 100644
index 00000000..0218bd66
--- /dev/null
+++ b/internal/character/ruanmei/technique.go
@@ -0,0 +1,8 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/key"
+)
+
+func (c *char) Technique(target key.TargetID, state info.ActionState) {}
diff --git a/internal/character/ruanmei/trace.go b/internal/character/ruanmei/trace.go
new file mode 100644
index 00000000..ecc37b30
--- /dev/null
+++ b/internal/character/ruanmei/trace.go
@@ -0,0 +1,72 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/engine/modifier"
+	"github.com/simimpact/srsim/pkg/engine/prop"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+const (
+	A2 = "ruanmei-a2"
+	A4 = "ruanmei-a4"
+	A6 = "ruanmei-a6"
+)
+
+func init() {
+	modifier.Register(A2, modifier.Config{
+		StatusType: model.StatusType_STATUS_BUFF,
+	})
+	modifier.Register(A4, modifier.Config{
+		Listeners: modifier.Listeners{
+			OnPhase1: doA4,
+		},
+	})
+	modifier.Register(A6, modifier.Config{
+		Listeners: modifier.Listeners{
+			OnPropertyChange: checkA6,
+		},
+	})
+}
+
+func (c *char) initTraces() {
+	if c.info.Traces["102"] {
+		c.engine.AddModifier(c.id, info.Modifier{
+			Name:   A4,
+			Source: c.id,
+		})
+	}
+}
+
+func doA4(mod *modifier.Instance) {
+	mod.Engine().ModifyEnergy(info.ModifyAttribute{
+		Key:    A4,
+		Target: mod.Source(),
+		Source: mod.Source(),
+		Amount: 5,
+	})
+}
+
+func checkA6(mod *modifier.Instance) {
+	// Calculate how much DMG Bonus should be given
+	rm, _ := mod.Engine().CharacterInfo(mod.Owner())
+	dmgAmt := skillDmg[rm.SkillLevelIndex()]
+	if rm.Traces["103"] {
+		dmgAmtA6 := 0.06 * float64(int((mod.OwnerStats().BreakEffect()-1.2)/0.1))
+		if dmgAmtA6 > 0.36 {
+			dmgAmtA6 = 0.36
+		}
+		dmgAmt += dmgAmtA6
+	}
+
+	// Reapply Overtone's DMG Bonus Buff to all allies with the new amount
+	for _, trg := range mod.Engine().Characters() {
+		if mod.Engine().HasModifier(trg, OvertoneDmgBuff) {
+			mod.Engine().AddModifier(trg, info.Modifier{
+				Name:   OvertoneDmgBuff,
+				Source: mod.Owner(),
+				Stats:  info.PropMap{prop.AllDamagePercent: dmgAmt},
+			})
+		}
+	}
+}
diff --git a/internal/character/ruanmei/ult.go b/internal/character/ruanmei/ult.go
new file mode 100644
index 00000000..68128305
--- /dev/null
+++ b/internal/character/ruanmei/ult.go
@@ -0,0 +1,221 @@
+package ruanmei
+
+import (
+	"github.com/simimpact/srsim/pkg/engine/event"
+	"github.com/simimpact/srsim/pkg/engine/info"
+	"github.com/simimpact/srsim/pkg/engine/modifier"
+	"github.com/simimpact/srsim/pkg/engine/prop"
+	"github.com/simimpact/srsim/pkg/key"
+	"github.com/simimpact/srsim/pkg/model"
+)
+
+const (
+	Ult           = "ruanmei-ult"
+	UltResPenAlly = "ruanmei-ult-res-pen-ally"
+	UltBuffAlly   = "ruanmei-ult-buff-ally"
+	UltDebuff     = "ruanmei-thanatopium-rebloom"
+	UltDebuffCD   = "ruanmei-thanatopium-rebloom-cooldown"
+)
+
+func init() {
+	// 2 mods summarized to 1 mod that represents both logic and visual/Buff status type
+	modifier.Register(Ult, modifier.Config{
+		Stacking:   modifier.ReplaceBySource,
+		StatusType: model.StatusType_STATUS_BUFF,
+		TickMoment: modifier.ModifierPhase1End,
+		Listeners: modifier.Listeners{
+			OnAdd:    addResPen,
+			OnRemove: removeUltMods,
+		},
+	})
+	// 2 mods summarized to 1 mod that represents both logic and visual/Buff status type
+	modifier.Register(UltResPenAlly, modifier.Config{
+		Stacking: modifier.Refresh,
+	})
+	// Purely for visual/Buff status type for other allies
+	modifier.Register(UltBuffAlly, modifier.Config{
+		Stacking:   modifier.ReplaceBySource,
+		StatusType: model.StatusType_STATUS_BUFF,
+	})
+	modifier.Register(UltDebuff, modifier.Config{
+		BehaviorFlags: []model.BehaviorFlag{model.BehaviorFlag_BREAK_EXTEND},
+		CanDispel:     true,
+		Listeners: modifier.Listeners{
+			// OnAllowAction: removeReset, (unknown mechanic, will be ignored)
+			OnHPChange:    removeCDAndSelf,
+			OnEndBreak:    doUltImprintWithRemove,
+			OnDispel:      removeCD,
+			OnBreakExtend: doUltImprint,
+		},
+	})
+	modifier.Register(UltDebuffCD, modifier.Config{
+		BehaviorFlags: []model.BehaviorFlag{model.BehaviorFlag_REMOVE_WHEN_SOURCE_DEAD},
+		Listeners: modifier.Listeners{
+			OnLimboWaitHeal: func(mod *modifier.Instance) bool {
+				mod.RemoveSelf()
+				return false
+			},
+			OnEndBreak: func(mod *modifier.Instance) {
+				mod.RemoveSelf()
+			},
+		},
+	})
+}
+
+func (c *char) initUlt() {
+	if c.info.Eidolon >= 1 {
+		// Apply E1 to allies created while Ult is active
+		c.engine.Events().CharactersAdded.Subscribe(func(event event.CharactersAdded) {
+			for _, char := range event.Characters {
+				trg := char.ID
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   E1,
+					Source: c.id,
+				})
+			}
+		})
+	}
+
+	// Apply UltDebuff with AttackEnd while RM has Ult
+	c.engine.Events().AttackEnd.Subscribe(func(event event.AttackEnd) {
+		if !c.engine.IsCharacter(event.Attacker) {
+			return
+		}
+		if c.engine.HasModifier(c.id, Ult) {
+			for _, trg := range event.Targets {
+				removeThisTurn := false
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   UltDebuff,
+					Source: c.id,
+					State:  &removeThisTurn,
+				})
+				c.engine.AddModifier(trg, info.Modifier{
+					Name:   UltDebuffCD,
+					Source: c.id,
+				})
+			}
+		}
+	})
+
+	// Remove UltDebuff if Imprint Damage was during this turn
+	c.engine.Events().TurnEnd.Subscribe(func(event event.TurnEnd) {
+		for _, trg := range c.engine.Enemies() {
+			if c.engine.HasModifierFromSource(trg, c.id, UltDebuff) {
+				// Get UltDebuff's dynamic value
+				mod := c.engine.GetModifiers(trg, UltDebuff)[0]
+				removeThisTurn := mod.State.(*bool)
+				if *removeThisTurn {
+					*removeThisTurn = false
+					c.engine.RemoveModifier(trg, UltDebuff)
+				}
+			}
+		}
+	})
+}
+
+func (c *char) Ult(target key.TargetID, state info.ActionState) {
+	durationUlt := 2
+	if c.info.Eidolon >= 6 {
+		durationUlt += 1
+	}
+	c.engine.AddModifier(c.id, info.Modifier{
+		Name:     Ult,
+		Source:   c.id,
+		Duration: durationUlt,
+		State:    ultResPen[c.info.UltLevelIndex()],
+	})
+	if c.info.Eidolon >= 1 {
+		for _, trg := range c.engine.Characters() {
+			c.engine.AddModifier(trg, info.Modifier{
+				Name:   E1,
+				Source: c.id,
+			})
+		}
+	}
+	for _, trg := range c.engine.Characters() {
+		c.engine.AddModifier(trg, info.Modifier{
+			Name:   UltBuffAlly,
+			Source: c.id,
+		})
+	}
+}
+
+func addResPen(mod *modifier.Instance) {
+	for _, trg := range mod.Engine().Characters() {
+		if trg == mod.Owner() {
+			mod.AddProperty(prop.AllDamagePEN, mod.State().(float64))
+		} else {
+			mod.Engine().AddModifier(trg, info.Modifier{
+				Name:   UltResPenAlly,
+				Source: mod.Owner(),
+				Stats:  info.PropMap{prop.AllDamagePEN: mod.State().(float64)},
+			})
+		}
+	}
+}
+
+func removeUltMods(mod *modifier.Instance) {
+	for _, trg := range mod.Engine().Characters() {
+		mod.Engine().RemoveModifier(trg, UltResPenAlly)
+		mod.Engine().RemoveModifier(trg, UltBuffAlly)
+		mod.Engine().RemoveModifier(trg, E1)
+	}
+}
+
+func removeCDAndSelf(mod *modifier.Instance, e event.HPChange) {
+	if mod.Engine().HPRatio(mod.Owner()) == 0 {
+		removeCD(mod)
+		mod.RemoveSelf()
+	}
+}
+
+func removeCD(mod *modifier.Instance) {
+	mod.Engine().RemoveModifier(mod.Owner(), UltDebuffCD)
+}
+
+func doUltImprintWithRemove(mod *modifier.Instance) {
+	doUltImprint(mod)
+	mod.Engine().RemoveModifier(mod.Owner(), UltDebuffCD)
+	mod.RemoveSelf()
+}
+
+func doUltImprint(mod *modifier.Instance) {
+	removeThisTurn := mod.State().(*bool)
+	*removeThisTurn = true
+
+	// Assumed to happen before insert
+	rm, _ := mod.Engine().CharacterInfo(mod.Source())
+	delayAmt := mod.Engine().Stats(mod.Source()).BreakEffect()*0.2 + 0.1
+	mult := ultBreakDamage[rm.UltLevelIndex()]
+	maxStanceMult := ((mod.Engine().MaxStance(mod.Owner()) / 30) + 2) / 4
+	mod.Engine().SetCurrentGaugeCost(info.ModifyCurrentGaugeCost{
+		Key:    UltDebuff,
+		Source: mod.Source(),
+		Amount: -1,
+	})
+
+	mod.Engine().InsertAbility(info.Insert{
+		Key: UltDebuff,
+		Execute: func() {
+			mod.Engine().Attack(info.Attack{
+				Key:          UltDebuff,
+				Targets:      []key.TargetID{mod.Owner()},
+				Source:       mod.Source(),
+				DamageType:   model.DamageType_ICE,
+				AttackType:   model.AttackType_ELEMENT_DAMAGE,
+				BaseDamage:   info.DamageMap{model.DamageFormula_BY_BREAK_DAMAGE: mult * maxStanceMult},
+				AsPureDamage: true,
+			})
+		},
+		Source:     mod.Source(),
+		AbortFlags: nil,
+		Priority:   info.CharInsertAttackSelf,
+	})
+
+	mod.Engine().ModifyGaugeNormalized(info.ModifyAttribute{
+		Key:    UltDebuff,
+		Target: mod.Owner(),
+		Source: mod.Source(),
+		Amount: delayAmt,
+	})
+}
diff --git a/pkg/key/character.go b/pkg/key/character.go
index dcf828e0..57f07d42 100644
--- a/pkg/key/character.go
+++ b/pkg/key/character.go
@@ -29,6 +29,7 @@ const (
 	March7th              Character = "march7th"
 	Seele                 Character = "seele"
 	Huohuo                Character = "huohuo"
+	RuanMei               Character = "ruanmei"
 	Xueyi                 Character = "Xueyi"
 )
 
diff --git a/pkg/simulation/imports.go b/pkg/simulation/imports.go
index a6e1aba6..855dbd2a 100644
--- a/pkg/simulation/imports.go
+++ b/pkg/simulation/imports.go
@@ -22,6 +22,7 @@ import (
 	_ "github.com/simimpact/srsim/internal/character/natasha"
 	_ "github.com/simimpact/srsim/internal/character/pela"
 	_ "github.com/simimpact/srsim/internal/character/qingque"
+	_ "github.com/simimpact/srsim/internal/character/ruanmei"
 	_ "github.com/simimpact/srsim/internal/character/sampo"
 	_ "github.com/simimpact/srsim/internal/character/seele"
 	_ "github.com/simimpact/srsim/internal/character/serval"