Image Credit: HoyoVerse

Dr. Ratio is a powerhouse single-target DPS who thrives on debuff synergy and follow-up attacks. With the right setup, he becomes an unstoppable force against bosses and elite enemies. He isn’t just smart—he’s lethal. In this build guide, I’ll show you how to turn his follow-up attacks into boss-slaying judgment calls.

Core Playstyle

Dr. Ratio’s strength lies in his Talent, Cogito, Ergo Sum, which grants a base 40% chance to trigger a follow-up attack after using his Skill. This chance increases by 20% for each debuff on the enemy, up to 100%. His Ultimate, Syllogistic Paradox, applies Wiseman’s Folly, enabling additional follow-up attacks when allies strike the afflicted target. This makes debuff-heavy team compositions ideal for maximizing his damage output.

​Best Build

Planar Ornaments: Duran, Dynasty of Running Wolves boosts follow-up attack damage and CRIT DMG when allies perform follow-up attacks. Inert Salsotto is another solid choice, enhancing Ultimate and follow-up attack damage when CRIT Rate exceeds 50%.

Light Cone: Baptism of Pure Thought is his signature Light Cone, boosting CRIT DMG and granting DEF ignore on follow-up attacks after using his Ultimate. For a more accessible option, Worrisome, Blissful increases CRIT Rate and follow-up attack damage, while applying the Tame debuff to enemies.

Relic Set: Pioneer Diver of Dead Waters (4-piece) enhances damage against debuffed enemies, synergizing perfectly with Dr. Ratio’s kit. Alternatively, Wastelander of Banditry Desert (4-piece) increases CRIT Rate and CRIT DMG against debuffed and Imprisoned enemies. ​

Main Stats:

• Body: CRIT Rate / CRIT DMG
• Feet: SPD or ATK%
• Sphere: Imaginary DMG
• Rope: ATK%

Sub Stats Priority: Focus on CRIT DMG, CRIT Rate, ATK%, and SPD.​

Trace Priority

1. Talent: Maximize for increased follow-up attack damage.
2. Ultimate: Enhances single-target burst potential.
3. Skill: Boosts base damage and applies debuffs.
4. Basic Attack: Lowest priority.

Team Compositions

Hypercarry Setup: Dr. Ratio, Ruan Mei, Pela, Luocha

• Dr. Ratio: Main DPS, capitalizing on follow-up attacks.
• Ruan Mei: Provides buffs and applies debuffs through her Ultimate.
• Pela: Reduces enemy DEF, enhancing Dr. Ratio’s damage.
• Luocha: Offers healing and removes enemy buffs.​

This composition focuses on maximizing Dr. Ratio’s damage output by ensuring enemies are consistently debuffed, allowing his follow-up attacks to trigger reliably.

Dual DPS Synergy: Dr. Ratio, Topaz, Silver Wolf, Huohuo

• Dr. Ratio: Primary DPS with strong follow-up attacks.
• Topaz: Enhances follow-up attack damage and applies debuffs.
• Silver Wolf: Inflicts multiple debuffs, increasing Dr. Ratio’s follow-up chances.
• Huohuo: Provides healing and energy regeneration.​

Topaz and Silver Wolf synergize well with Dr. Ratio by applying debuffs that boost his follow-up attack probability and damage. Huohuo ensures team sustainability.

Mono-Imaginary Team: Dr. Ratio, Welt, Yukong, Luocha

• Dr. Ratio: Main DPS dealing Imaginary damage.
• Welt: Applies debuffs and controls enemy actions.
• Yukong: Boosts CRIT stats and Imaginary damage.
• Aventurine: Shields and performs follow-up attacks.​

This team leverages Imaginary element synergy, with Welt and Yukong enhancing Dr. Ratio’s damage potential, while Aventurine sustains the team while performing follow-up attacks.

Free-to-Play Friendly: Dr. Ratio, Asta, March 7th, Natasha

• Dr. Ratio: Primary DPS.
• Asta: Increases team SPD and applies Burn debuff.
• March 7th: Provides shields and counterattacks.
• Natasha: Offers healing support.​

This accessible team setup ensures Dr. Ratio benefits from SPD boosts and enemy debuffs, enhancing his follow-up attack frequency.

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