Dr Ratio is an Imaginary and Hunt character in Honkai: Star Rail. Check out this guide for Dr. Ratio's best builds, team comps, relics, light cones, kit, and Materials here!

Dr. Ratio Character Information

Dr. Ratio Basic Info and Rating

Dr. Ratio Basic Information
Dr. Ratio	Rarity	5-star
	Element	Imaginary
	Path	Hunt
General Rating		Endgame Rating
Overall DPS		MoC PF AS

Ratings are based on E0.

How do you rate Dr. Ratio?

Character Tier List

Dr. Ratio Stats

Is Dr. Ratio Good?

Dr. Ratio is one of the most powerful units in terms of dealing single-target DMG. His strong Follow-up attacks are most effective against Bosses and can become a lot stronger if enemies are affected by debuffs.

Dr. Ratio is worth building if you need a strong boss-killer who specializes in Follow-up Attacks!

Dr. Ratio's Best Builds

Imaginary DPS Build

Dr. Ratio's best build is pretty straightforward as Pioneer Diver of Dead Waters will increase his DMG on debuffed enemies. The 4pc. effect can be boosted after Dr. Ratio uses his Ultimate.

Duran, Dynasty of Running Wolves will increase Dr. Ratio's Follow-up Attack DMG and CRIT DMG as long as allies use Follow-up attacks.

Recommended Stat Values

Stat	Recommended Value
CRIT Rate	70% or above (Outside of combat)
CRIT DMG	150% or above (Outside of combat)
ATK	2600 or above
SPD	134

Dr. Ratio's Best Teams

Dr. Ratio F2P Team (Free to Play)

DPS	Support	Support	Healer
Dr. Ratio	March 7th (Imaginary)	Asta	Natasha

This free-to-play team is your typical Hypercarry setup where Dr. Ratio is the Main DPS. March 7th can provide additional buffs and DMG while Asta can buff his SPD and has a chance to Burn the enemy.

Dr. Ratio Generalist Team

DPS	Sub-DPS	Support	Sustain
Dr. Ratio	Topaz	Robin	Aventurine
Dr. Ratio	Topaz	Silver Wolf	Luocha

Dr. Ratio's best teams typically consist of a buffer and a debuffer, with the latter being especially important for Dr. Ratio's Follow-up Attacks.

Topaz has amazing synergy with Dr. Ratio as she can provide additional DMG and increase his Follow-up Attack DMG.

If you have Aventurine, you can use Robin as your second Support unit to increase overall Follow-up attack DMG. Otherwise, use Silver Wolf to implant a lot of debuffs on the enemy.

Dr. Ratio Mono-Imaginary Team

DPS	Support	Support	Shielder
Dr. Ratio	March 7th (Imaginary)	Silver Wolf	Aventurine

This Dr. Ratio team comp is viable in certain content where the enemy is weak to Quantum but not to Imaginary. Silver Wolf is a must-have for this team so she can implant an Imaginary Weakness on an enemy.

If the enemy is already weak to Imaginary, you can replace Silver Wolf with another debuffer.

Dr. Ratio's Best Relics and Ornaments

All Recommended Relics and Ornaments

Relics	Rating & Merits
Pioneer Diver of Dead Waters x4	★★★★★ - Best Pioneer Diver of Dead Waters is Dr. Ratio's best-in-slot relic set as it increases his DMG on debuffed enemies. Dr. Ratio can provide his own debuff, which further enhances his DMG.
Wastelander of Banditry Desert x4	★★★★☆ - 2nd Best Wastelander of Banditry Desert is great for Dr. Ratio as it increases his CRIT if the target enemy is debuffed or Imprisoned. This is especially great if you have a debuffer at the party.
The Wind-Soaring Valorous x4	★★★☆☆ - 3rd Best The Wind-Soaring Valorous is a decent set to use since Dr. Ratio uses Follow-up attacks and can deal damage with his Ultimate.
Ornaments	Merits
Duran, Dynasty of Running Wolves	★★★★★ - Best Duran, Dynasty of Running Wolves is Ratio's new best-in-slot since it can provide Follow-up Attack and CRIT DMG buffs as long as allies use Follow-up attacks.
Inert Salsotto	★★★★☆ - 2nd Best Inert Salsotto is a great ornament for Dr. Ratio as it increases his Follow-up attacks and Ultimate DMG. The CRIT Rate threshold should be easy to achieve thanks to Dr. Ratio's CRIT Rate buffs from his Traces.
Izumo Gensei and Takama Divine Realm	★★★☆☆ - 3rd Best Izumo Gensei is best used when another Hunt character is used on Dr. Ratio's team. This gives a huge CRIT Rate boost to Dr. Ratio.

Relic List & Guide

Dr. Ratio's Best Light Cones

All Recommended Light Cones

Light Cone	Why We Recommend It
Baptism of Pure Thought	★★★★★ - Best Baptism of Pure Thought is the best for Dr. Ratio since it directly increases his DMG. It also gives his Follow-Up Attacks DEF ignore after using his Ultimate, where he can make additional Follow-Up Attacks with this buff on.
Worrisome, Blissful	★★★★☆ - Great Worrisome, Blissful is also a great option for Dr. Ratio since it increases his CRIT Rate and Follow-Up Attack DMG. It also provides the Tame debuff to enemy targets, which increases the CRIT DMG dealt by allies who attack them.
In the Night	★★★★☆ - Great In the Night is also a great Light Cone option for Dr. Ratio since it increases his CRIT Rate. It also increases the DMG of his Basic ATK, Skill, and CRIT DMG of his Ultimate based on his SPD.
Sleep Like the Dead	★★★☆☆ - Good Sleep Like the Dead is a good 5-Star Light Cone option for Dr. Ratio since it boosts his CRIT DMG and boosts his CRIT Rate if his Skill or Basic ATK doesn't crit.
Cruising in the Stellar Sea	★★★☆☆ - Good Cruising in the Stellar Sea is a good Light Cone for Dr. Ratio since it increases his CRIT Rate and provides an ATK boost whenever he defeats an enemy.
Swordplay	★★★☆☆ - Good Swordplay is a good Light Cone for Dr. Ratio since it gives him a stacking DMG boost as long as he keeps attacking a single enemy target. This can easily ramp up thanks to his Follow-Up Attacks and works well against bosses.

Light Cone List & Guide

Dr. Ratio's Gameplay Guide

Back to Dr. Ratio Builds ▲

Dr. Ratio Trace Priority

Trace	Priority & Explanation
Basic Attack	★☆☆☆☆ - Lowest Priority Dr. Ratio's Basic ATKs can be left out as his Skill deals a lot more DMG.
Skill	★★★★☆ - High Priority Upgrading Dr. Ratio's Skill simply increases its DMG. This is Dr. Ratio's go-to Trace if his Ultimate isn't up yet.
Ultimate	★★★★☆ - High Priority Upgrading Dr. Ratio's Ultimate simply increases its DMG. This deals a massive amount of DMG to an enemy.
Talent	★★★★★ - Highest Priority Majority of Dr. Ratio's DMG will come from his Follow-up attacks. Upgrading Dr. Ratio's Talent will increase his Follow-up attack DMG.

See All Traces ▼

Dr. Ratio Recommended Eidolons

	Why We Recommend It
E1	★★★★★ - Amazing Dr. Ratio's attacks against debuffed enemies get an automatic increase of CRIT Rate by 10% and CRIT DMG by 20%. His Summation stacks can go up to 10, which can provide him up to 25% CRIT Rate and 50% CRIT DMG.
E2	★★★★★ - Amazing A great stopping point to make the most out of Dr. Ratio. Dr. Ratio's Follow-up Attacks deal additional DMG depending on the amount of debuffs an enemy has.
E4	★★★☆☆ - Good Dr. Ratio's restores energy every time he unleashes a Follow-up attack. A minor buff to Dr. Ratio's Ultimate usage.
E6	★★★★☆ - Great Dr. Ratio's Follow-up attack DMG gets increased and his Ultimate gets an extra Wiseman's Folly count.

See All Eidolons ▼

Skill Deals Single Target DMG and Debuffs Enemies

Dr. Ratio's Skill deals Imaginary DMG to one enemy and debuffs them. His Skill also has great synergy with his Talent, since it allows him to do a Follow-Up Attack at a certain chance after using his Skill.

Talent Allows Him to Use Follow-Up Attack on Debuffed Enemies

Dr. Ratio has a 40% base chance of launching a Follow-Up attack on a single target after using his Skill. For each debuff the target enemy has, the fixed chance of launching the Follow-up attack can increase up to 100%. This means that Dr. Ratio will work well with Nihility characters!

If an enemy is defeated right before Dr. Ratio launches a Follow-up attack on said target, he will attack a random enemy instead.

Ultimate Helps Launch Additional Follow-Ups

Dr. Ratio's Ultimate deals Imaginary DMG to a single enemy target and applies Wiseman's Folly. When all other allies attack targets affected with Wiseman's Folly, Dr. Ratio will launch a Follow-up attack on them.

Technique Taunts Enemies and Reduces Their SPD

Dr. Ratio's Technique can create a special dimension that Taunts nearby enemies. After entering battle with enemies in the dimension, there is a base chance to reduce the enemies' SPD.

Dr. Ratio's Traces (Skills and Kit)

See Trace Priority ▲

All Abilities and Effects

Trace	Scaling and Explanation
Skill	Intellectual Midwifery: Deals 75% of Dr. Ratio's ATK as Imaginary DMG to a single target enemy. Stat Bonus: 1. ATK +6.0%
Talent	Cogito, Ergo Sum: When using his Skill, Dr. Ratio has a 40% fixed chance of launching a follow-up attack against his target for 1 time, dealing Imaginary DMG equal to 135% of Dr. Ratio's ATK. For each debuff the target enemy has, the fixed chance of launching follow-up attack increases by 20%. If the target enemy is defeated before the follow-up attack triggers, the follow-up attack will be directed at a single random enemy instead.
Ultimate	Syllogistic Paradox: Deals Imaginary DMG equal to 144% of Dr. Ratio's ATK to a single target enemy and applies Wiseman's Folly. When Dr. Ratio's allies attack a target afflicted with Wiseman's Folly, Dr. Ratio launches his Talent's follow-up attack for 1 time against this target. Wiseman's Folly can be triggered for up to 2 times and only affects the most recent target of Dr. Ratio's Ultimate. This trigger count resets after Dr. Ratio's Ultimate is used.
Technique	Mold of Idolatry: After using Technique, creates a special dimension that Taunts nearby enemies, lasting for 10 second(s). After entering battle with enemies in this special dimension, there is a 100% base chance to reduce each single enemy target's SPD by 15% for 2 turn(s). Only 1 dimension created by allies can exist at the same time. Stat Bonus: 1. ATK +4.0%
Basic ATK	Mind is Might: Deals 50% of Dr. Ratio's ATK as Imaginary DMG to a single target enemy. Stat Bonus: 1. DEF +5.0%
Bonus Ability	Summation: When Dr. Ratio uses his Skill, for every debuff on the target, his CRIT Rate increases by 2.5% and CRIT DMG by 5%. This effect can stack up to 6 time(s). Stat Bonus: 1. CRIT Rate +2.7% 2. ATK +2.0%
Bonus Ability	Inference: When Skill is used to attack an enemy target, there is a 100% base chance to reduce the attacked target's Effect RES by 10% for 2 turn(s). Stat Bonus: 1. ATK +6.0% 2. CRIT Rate +4.0%
Bonus Ability	Deduction: When dealing DMG to a target that has 3 or more debuff(s), for each debuff the target has, the DMG dealt by Dr. Ratio to this target increases by 10%, up to a maximum increase of 50%. Stat Bonus: 1. DEF +7.5% 2. CRIT Rate +5.3% 3. ATK +8.0%

Dr. Ratio's Eidolons

See Recommended Eidolons ▲

All Eidolon Resonance Effects

E1	Pride Comes Before a Fall The maximum stackable count for the Trace "Summation" increases by 4. When a battle begins, immediately obtains 4 stacks of Summation. Needs to unlock Summation first.
E2	The Divine Is in the Details When his Talent's follow-up attack hits a target, for every debuff the target has, additionally deals Imaginary Additional DMG equal to 20% of Dr. Ratio's ATK. This effect can be triggered for a maximum of 4 time(s) during each follow-up attack.
E3	Know Thyself Ultimate Lv. +2, up to a maximum of Lv. 15. Basic ATK Lv. +1, up to a maximum of Lv. 10.
E4	Ignorance is Blight When triggering the Talent, additionally regenerates 15 Energy for Dr. Ratio.
E5	Sic Itur Ad Astra Skill Lv. +2, up to a maximum of Lv. 15. Talent Lv. +2, up to a maximum of Lv. 15.
E6	Vincit Omnia Veritas Additionally increases the triggerable count for Wiseman's Folly by 1. The DMG dealt by the Talent's follow-up attack increases by 50%.

Dr. Ratio Ascension and Trace Materials

Total Ascension Materials

Ascension Materials	Total
Thief's Instinct	15
Usurper's Scheme	15
Conqueror's Will	15
Suppressing Edict	65
Credit	308,000

Total Trace Materials

All Trace Node Materials	Total
Arrow of the Beast Hunter	15
Thief's Instinct	41
Arrow of the Demon Slayer	72
Usurper's Scheme	56
Arrow of the Starchaser	139
Conqueror's Will	58
Past Evils of the Borehole Planet Disaster	12
Tracks of Destiny	11
Credit	3,000,000

Additional Dr. Ratio Information

How to Get Dr. Ratio

Claim for Free via Mail

Dr. Ratio is a free limited 5-star who you can claim via Mail from Jan. 17, 2024, until the end of Version 2.1.

How to Get Free Dr. Ratio

Pull From Limited Banners

Limited Banners
Panta Rhei

You can also get Dr. Ratio by pulling in the Character Warp banner called Panta Rhei which is available from Jan. 17, 2024, until Feb. 5, 2024.

Dr Ratio Banner Schedule and Rates

Background and Voice Actors

Voice Actor	EN: Jordan Paul Haro JP: Shunsuke Takeuchi
Faction / Affiliation	Intelligentsia Guild

Dr. Ratio's In-Game Lore

Faction	Intelligentsia Guild
Background	Member of the Intelligentsia Guild. Eccentric temperament, sharp-tongued but with an elegant demeanor. The face under the strange plaster head sculpture is apparently unexpectedly handsome.

Honkai: Star Rail Related Guides

▶︎ All Playable Characters

Characters by Rarity

Character Rarity
★★★★	★★★★★

Characters by Path

Character Paths
Destruction	The Hunt	Erudition	Harmony
Nihility	Preservation	Abundance	Remembrance

Characters by Element

Character Elements
Fire	Ice	Lightning	Wind
Quantum	Imaginary	Physical

All Imaginary Characters

Imaginary Characters
Luocha	Welt	Yukong	Imbibitor Lunae
Dr. Ratio	Aventurine	Trailblazer (Imaginary)	March 7th (Imaginary)
Rappa	Sunday