The good doctor has finally arrived in Honkai: Star Rail. Dr. Ratio was distributed for free for all players, and being one of the few easily accessible Imaginary units, chances are that you’ll build him at one time or another, so here’s what you should do for that.
Dr. Ratio Overview and Team Role in Honkai: Star Rail
Dr. Ratio is a 5-star Imaginary Hunt unit, and his gameplay revolves around his Talent. Whenever he attacks, there’s a 45% chance that he’ll throw a follow-up attack immediately at his target. However, for each debuff applied on the target after the attack is finished, the chance increases by 20%. His own Skill also applies a debuff.
With enough debuffers on his team, he becomes an unstoppable follow-up machine delivering knowledge to every opposing creature. This leads to him taking a Main DPS role in a team, but he can easily be slotted in dual-carry comps if paired with certain characters.
He’s also an Imaginary character released while the element itself isn’t easy to get. As of 1.6, Yukong is the only 4-star Imaginary character in the game, and she’s ironically best used with more Imaginary units on her team. Enter doctor Veritas Ratio as a free option for those who didn’t pull for Welt, Luocha or DHIL. And he’s a pretty damn good option, to say the least.
Traces Leveling Order & Eidolons
Focus Talent > Skill > Ultimate > Basic Attacks. Leveling his talent increases his follow-up attack damage, which is the core of his kit. He should also use his Skill whenever possible, so that’s the next priority. His Ultimate allows for easier follow-ups but isn’t the biggest priority, while his autos can be neglected with no harm done to his overall damage.
| Major Trace Name | Description |
| Summation (A2) | 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). |
| Inference (A4) | 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). |
| Deduction (A6) | 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%. |
All of his Ascension Traces contribute immensely to his kit, so unlock those ASAP. A6 is probably the most impactful, so make sure you got that one leveled first, if possible. He also gets a ton of free Critical Rate from passive Traces and from A2, so building him ends up being slightly easier.
While we already get him for free, his Eidolons are equally incredible, if you decide to invest them for some reason. I’d recommend getting his signature Light Cone instead, but they’re also quite impactful for Ratio.
| Eidolon Name | Description |
| 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. |
| 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. |
| Know Thyself | Ultimate Lv. +2, up to a maximum of Lv. 15. Basic ATK Lv. +1, up to a maximum of Lv. 10. |
| Ignorance Is Blight | When triggering the Talent, additionally regenerates 15 Energy for Dr. Ratio. |
| Sic Itur Ad Astra | Skill Lv. +2, up to a maximum of Lv. 15. Talent Lv. +2, up to a maximum of Lv. 15. |
| Vincit Omnia Veritas | Increases the trigger count for Wiseman’s Folly by 1. The DMG dealt by the Talent’s follow-up attack increases by 50%. |
E1 and E2 are very impactful and either of them is a good stopping point, but E6 is just insanely strong. But again, E0 Ratio is already very powerful, so don’t bother with extra copies if you’re saving for upcoming characters.
Best Relic Sets for Dr. Ratio
As of 1.6, Ratio doesn’t have any specific set tailor-made for him, but there are plenty of good options available as always. The desired main statuses are listed below in their priority order.
| Set Piece | Main Stat |
| Body | Critical Damage / Critical Rate% |
| Boots | Speed / Atk% |
| Sphere | Imaginary DMG% / Atk% (depending on teams/buffs) |
| Link Rope | Atk% |
For substats, aim for Critical Rate/Damage > Speed > Attack. Break Effect is okay, but not that desired. Try to reach a 70%/140% Critical Rate/Damage ratio, but always keep in mind his A2’s extra stats when balancing his equipment.
1 – 2pc Ashblazing Grand Duke + 2pc Wastelander of Banditry Desert
The most versatile set for Ratio is combining both Imaginary and Follow-up attack bonuses. Wastelander’s cavern might not be the best one to farm for most accounts, so you can try to get some pieces through Synthesis if you’re also building follow-up-based attackers/DoT units.
2 – 2pc Wastelander of Banditry Desert + 2pc Musketeer of Wild Wheat/Prisoner in Deep Confinement
Alternatively, Attack + Imaginary is also great for him, although he really enjoys that follow-up bonus. It makes his Skill/Ultimate a bit better, at least.
3 – 4pc Wastelander of Banditry Desert
The full set effect depends on having your opponent Imprisioned, which isn’t hard but isn’t that easy either, especially if Ratio is your only Imaginary unit. More of a niche option, but great if you always pair him with Welt.
4 – 4pc Genius of Brillant Stars
The universal set for any DPS as its DEF-ignore effect is incredibly powerful. Possibly stronger than any other option, but also harder to farm due to a less effective Cave. Really shines if you pair him with Silver Wolf.
As for Planar Ornaments, his best option is Innert Salsotto as it increases his follow-up attack’s damage after you get enough Critical Rate. Sealing Space Station and Firmament Frontline: Glamoth are also great options if you have good enough parts, too.
Best Light Cones for Dr. Ratio
Unfortunately, most non-signature Hunt Light Cones are not that great, but there are some good options if you’re not already using them on other characters.
1 – Baptism of Pure Thought
His signature cone provides him with everything he needs. More Critical Damage, good base stats, and incredible extra effects if the target is debuffed. If you have some extra Jades and are really doubling down on Ratio, getting his Cone is probably a better (and cheaper) option than going for Eidolons.
2 – Worrysome, Blissful
Topaz’s cone works wonders for him as it allows Ratio to inflict an extra debuff by himself. But if you have that LC, you probably also have Topaz, who should be the one to hold this LC as she’s one of the best teammates for Ratio.
3 – Cruising in the Stellar Sea
Herta’s shop option is simple but effective for Ratio. It gives him some free stats while also getting him some extra damage that stacks up after defeating enemies. Easy to Superimpose to 5 too.
4 – In the Night
Seele’s LC is a similar case to Topaz’s, but if you’re not using your Seele as often, Ratio can make good use of it as both characters have little to no synergy.
5 – Swordplay
One of the best 4-star Cones in the game, which really shines when fighting bosses. And since Hunt’s all about that sweet single-target potential, you should be fine with it as long as you’re not forced to change your target during a fight.
Other good options include Return to Darkness (Battle Pass Light Cone) and Sleep Like the Dead (Yanqing’s signature), but these require some important resources that can probably be spent elsewhere. But if you happen to have them for some reason, Ratio will be glad with these.
Best Dr. Ratio Teams and Compositions
Ratio needs more debuffs on his targets to achieve his full potential, so it’s almost mandatory to include at least one Nihility character to do just that. Silver Wolf is one of his best partners as her attacks can inflict two debuffs at once. Pela is also great for that, especially when wearing the Resolution Shines Light Cone.
Guinaifen, while a more niche pick, can also work thanks to Firekiss (Although she’s more desired on a Kafka team). But the best Fire unit to pair with him is definitely Topaz. Her Proof of Debt debuff helps Ratio immensely, and both DPS will enable each other by simply using their follow-ups. If she has her LC, the two of them are enough to give Ratio a 100% proc rate on his Talent.
Ratio is great with all Harmony units in the game too, as all of them can give him an edge at something. Tingyun, Bronya, and Ruan Mei in particular are great for him. Yukong also works great as she’ll increase his Imaginary damage.
Speaking of which, a full Imaginary comp is fully viable (although expensive) with Welt, Luocha, and Yukong. It has weirdly good synergy with buffs, debuffs, and heals, but be ready for a very SP-heavy playstyle.
Dr. Ratio is an amazing addition to the game’s roster, and being entirely free for players is still unbelievably great as he has a huge damage potential. Don’t sleep on the Doctor or his classes, unless you want to be a target for a stray chalk. And even if you build him later, he’ll probably still be relevant in future banners due to his great synergy with debuffs.
