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Dr Ratio is a five-star Imaginary Hunt character who can take a multitude of Light Cones and Relics due to his kit. Here is a guide on how to make your Dr Ratio shine in battle.
For starters, we need to understand how Dr Ratio works before we can decide what Light Cones or Relics to give him. He is a single-target attacker whose bread and butter revolves around follow-up attacks. For every debuff an enemy has, he has an increased chance of launching a follow-up attack on them. He also works best against enemies with high HP, due to the fact that he can trigger two “free” follow-up attacks so long as his allies target the enemy he hit with his Ultimate.
Best Light Cones for Dr Ratio in Honkai: Star Rail
- Baptism of Pure Thought
Obviously, Dr Ratio’s signature Light Cone is best for him. It boosts his Crit DMG, increasing for every debuff the enemy has. After he uses his Ultimate, his follow-up attacks can ignore target DEF for two turns. These effects mesh perfectly with his kit and due to the passive Crit DMG boost, it alleviates some of the pressure you might have with your Relics when building him. - Worrisome, Blissful
This is Topaz’s signature Light Cone, so it’s not a surprise that Dr Ratio can make heavy use of it too. Both of them heavily use follow-up attacks in their kit. This grants a Crit Rate and follow-up attack DMG bonus. This one is arguably a bit better if you’re using him with a sub-DPS because he can impart Tame stacks after he hits an enemy with a follow-up attack. Tame stacks will increase how much an ally’s Crit DMG hits for. - In the Night
This is Seele’s signature Light Cone and it happens to be a very good Light Cone for general Hunt use. It increases the user’s Crit Rate, as well as their Basic ATK, Skill DMG, and Ultimate Crit DMG based on a portion of their SPD. Since you’ll want Dr Ratio to have decent SPD anyway, this meshes well with how you’ll build him. - Only Silence Remains
Only Silence Remains boosts Dr Ratio’s ATK. It can also increase his Crit Rate if there are two or less enemies on the field. If you plan on bringing Dr Ratio into battles that might have more than that number, Return to Darkness is also a good Light Cone with a passive Crit Rate boost. - Swordplay
Swordplay is, like In the Night, a good general use Hunt Light Cone that is more readily available. It increases how much damage the wearer deals when they hit the same target. Considering Dr Ratio works best in single-target battles with an enemy that has lots of HP, you can get a lot of use from Swordplay.
Best Relics for Dr Ratio in Honkai: Star Rail
- 4-pc Pioneer Diver of Dead Waters
This is, as of Version 2.2, the best-in-slot set for Dr Ratio. It works very well with his kit, as he should always attack enemies with at least a single debuff on them. The damage difference between Pioneer and any other set is pretty astronomical, so if you want to use Dr Ratio as a solo DPS, you should consider farming this set. - 4-pc Wastelander of Banditry Desert
This is a great set due to its 4-pc effect. It increases his Crit Rate against debuffed enemies and Crit DMG against Imprisoned enemies. Due to the nature of his kit, you’ll definitely want to debuff enemies as often as possible, so the 4-pc set will benefit him the most - 2-pc Wastelander of Banditry Desert, 2-pc The Ashblazing Grand Duke
This is a good combination set for those who can’t put together a full set of Banditry. The 2-pc effect for Grand Duke increases how much damage his follow-up attack deals. If you want to run Dr Ratio with a non-Imaginary Nihility and he naturally has enough Crit Rate, this set works just as well as a 4-pc Banditry set. - Inert Salsotto
Inert Salsotto is the best Planar Ornament set for Dr Ratio since it increases both his follow-up attack and Ultimate DMG. It has a Crit Rate threshold of 50%. However, you can likely get to that number through his Traces and Light Cone even if you’re unlucky with Relics. - Firmament Frontline Glamoth
This is a good Planar Ornament set due to its ATK stat. He can also deal more DMG depending on his SPD (135/160), which plays well with how you’ll want to build him anyway.
Honkai: Star Rail is readily available on the PS5, Windows PC, and mobile devices. Between Versions 1.6 and 2.1, players can get Dr Ratio for free. He is also in the gacha, but you can only pull for him while the “Panta Rhei” Character Event Warp is active.
