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Honkai: Star Rail – Dr. Ratio build and ascension guide

Check out the best Light Cones and Relics for Dr. Ratio in Honkai: Star Rail
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Become an insufferable lord of memes with the best Honkai: Star Rail Dr. Ratio build and show all of your detrimentors the L – and do all of it for free. Anyone playing between version 1.6 and 2.1 is able to claim a free Dr. Ratio, adding the 5-Star character following the Path of The Hunt and dealing Imaginary Damage to their arsenal.

Dr. Ratio’s Skill, Intellectual Midwifery, deals Imaginary Damage to a single target. His Talent, Cogito, Ergo Sum, gives him a fixed 40% chance to launch a follow-up attack after using his Skill, against the same target dealing Imaginary Damage. Both are based on his Attack stat. Each debuff on the target increases the chance to launch a follow-up attack by 20%.

Honkai: Star Rail artwork of Dr. Ratio on space background.

Ready to get educated the Dr. Ratio way?

His Ultimate, Syllogistic Paradox, deals Imaginary Damage based on his Attack to a single target and applies Wiseman’s Folly. If Dr. Ratio’s allies attack an enemy affected by Wiseman’s Folly, he’ll use his follow-up attack against this target. This can be triggered two times and only affects the latest enemy to be hit by his Ultimate.

Dr. Ratio’s Eidolon Levels, which are obtained by pulling additional copies of him, further boost his effectiveness. Eidolon 1 allows him to stack additional buffs from his Summation Trace and Eidolon 2 enables his follow-up attack to deal additional damage for each debuff on the target. Eidolon 4 regenerates Energy for Dr. Ratio when his Talent is used. Finally, Eidolon 6 increases the amount of times Wiseman’s Folly can be triggered by one. In addition, his follow-up attack’s damage is increased by a staggering 50%.

Honkai: Star Rail – Dr. Ratio: best Light Cones

Dr. Ratio has a signature Light Cone, which is called Baptism of Pure Thought and provides a powerful boost to Critical Hit Rate. In addition, it increases the wearer’s Critical Hit Damage for every debuff on the enemy target, stacking up to three times. When using their Ultimate, the wielder receives the Disputation effect for two turns, which increases the overall damage dealt by them as well as allowing their follow-up attacks to partially ignore the enemy’s Defense.

This is a beastly offensive Light Cone that perfectly complements Ratio’s playstyle.

Best Light Cones for Dr. Ratio:

  • Baptism of Pure Thought (5-Star)
  • Worrisome, Blissful (5-Star)
  • Cruising in the Stellar Sea (5-Star)
  • Sleep Like the Dead (5-Star)
  • Return to Darkness (4-Star)
  • Subscribe for More! (4-Star)
Honkai: Star Rail Dr. Ratio in a bathtub.

Dr. Ratio is a man of refinement and culture.

Honkai: Star Rail – Dr. Ratio: best Relics

Dr. Ratio requires more Attack, Critical Hit Rate, and Critical Hit Damage to maximize his DPS output. Boosting his follow-up attack damage is a good idea as well, since that's is ultimately where most of his damage is coming from.

Best Relic Sets for Dr. Ratio:

  • Pioneer Diver of Dead Waters (4) – +12% damage dealt to debuffed enemies, +4% Critical Hit Rate and 8%/12% increased Critical Hit Damage against enemies with at least 2/3 debuffs. After the wearer inflicts a debuff on enemy targets, these effects increase by 100% for one turn.
  • Wastelander of Banditry Desert (4) – +10% Imaginary Damage, +10% Critical Hit Rate, +20% Critical Hit Damage when attacking Imprisoned enemies.
  • The Ashblazing Grand Duke (4) – +20% follow-up attack damage, +6% Attack whenever the wearer’s follow-up attack deals damage; this effect stacks up to eight times, lasts for three turns, and is removed the next time a follow-up attack is used.

Best Planar Ornaments for Dr. Ratio:

  • Inert Salsotto (2) – +8% Critical Hit Rate, +15% Ultimate and follow-up attack damage when the wearer’s Critical Hit Rate surpasses 50%.

Prioritize the following Relic and Planar Ornament stats for Dr. Ratio:

  • Head – HP (Primary), Critical Hit Rate %, Critical Hit Damage %, Attack %, Speed
  • Hands – Attack (Primary), Critical Hit Rate %, Critical Hit Damage %, Attack %, Speed
  • Body – Critical Hit Rate % (Primary), Critical Hit Damage %, Attack %, Speed, Break Effect %
  • Feet – Speed (Primary), Critical Hit Rate %, Critical Hit Damage %, Attack %, Break Effect %
  • Planar Sphere – Imaginary Damage % (Primary), Critical Hit Rate %, Critical Hit Damage %, Attack %, Speed
  • Link Rope – Attack % (Primary), Critical Hit Rate %, Critical Hit Damage %, Speed, Break Effect %
Honkai: Star Rail screenshot showing a first-person view of a hand and a book.

L + Ratio, nerds.

Honkai: Star Rail – Dr. Ratio: best teams

Using Dr. Ratio to his full effect requires you to bring a character that can debuff the enemy, which will enable the damage dealer to consistently unleash follow-up attacks.

Silver Wolf can easily inflict debuffs on enemies, allowing Dr. Ratio to take them out with his follow-up attacks. Yukong is a strong support for Imaginary Damage characters, tuning those critical stats even higher. Fill the sustain slot with whomever you have available, as usual.

Pela is another fantastic debuffer you should keep in mind for Dr. Ratio, while the usual cast of supports like Bronya, Tingyun, Asta or Ruan Mei are all strong with the intellectual as well. If you have Topaz at Eidolon 1, she can be considered a potent support for Dr. Ratio as well.

Honkai: Star Rail Dr. Ratio slapping someone with a book.

Dr. Ratio goes around slapping people with his thick book.

Honkai: Star Rail – Dr. Ratio: ascension materials

Here’s everything you need to know to get Dr. Ratio ascended to the maximum level and upgrade all of his talents.

Dr. Ratio requires the following ascension materials to get to level 80 in addition to the necessary XP:

  • Credits x308,000
  • Thief’s Instinct x15
  • Usurper’s Scheme x15
  • Conqueror's Will x15
  • Suppressing Edict x65

You can collect Thief’s Instinct, Usurper’s Scheme, and Conqueror's Will from Legion enemies on Herta Space Station as well as the Simulated Universe. You can create or exchange them through the Omni-Synthesizer on the Astral Express, too. Thief’s Instinct is one of the base materials you can easily farm through the Daily Assignments to your characters, making for a steady income of the material. Suppressing Edicts are dropped by the Stagnant Shadow in the Artisanship Commission or gained through the exchange of similarly rare materials. The best source of Credits are the Golden Calyxes found around the galaxy.

Honkai: Star Rail Dr. Ratio doing the L + Ratio gesture.

Bow down to the lord of memes.

Dr. Ratio requires the following materials to upgrade her combat abilities and Traces:

  • Credits x3,000,000
  • Thief’s Instinct x41
  • Usurper’s Scheme x56
  • Conqueror's Will x58
  • Arrow of the Beast Hunter x18
  • Arrow of the Demon Slayer x69
  • Arrow of the Starchaser x139
  • Past Evils of the Borehole Planet Disaster x12
  • Tracks of Destiny x8

For the materials already mentioned, check above. Arrows can be farmed in the Crimson Calyx on the Outlying Snow Plains. As usual, you can create the high-level materials by using lower-level materials in the Omni-Synthesizer on the Astral Express.

Past Evils of the Borehole Planet Disaster is a boss material only gained from the Echo of War (Seclusion Zone) domain, while Tracks of Destiny can be obtained during time-limited events, the Embers Exchange, the Nameless Honor, or as a Simulated Universe Points Reward.