Dr. Ratio is a powerful free character available in Honkai Star Rail. He is a member of The Hunt Path, making him great for single-target damage against bosses. He also specializes in follow-up attacks and debuffing the same target multiple times.

Dr. Ratio is free as part of Honkai Star Rail's 1.6 update. This promotional deal will last until the release of patch 2.1, but no official date has been announced. After that period, Dr. Ratio will likely enter a random “Warp” gacha draw. While some players might still gain him for free, the chance will no longer be guaranteed.

How To Get Dr. Ratio For Free In Honkai: Star Rail

Dr. Ratio is unlocked via the in-game Mail system. For existing players, this will be as simple as opening their latest messages and accepting the attachment to recruit Dr. Ratio. The standard Warp animation will play, and he will become a selectable party member.

However, new s will need to unlock the Mail feature entirely. This may be true for many new PlayStation 5 players on Honkai: Star Rail who haven’t progressed much in the story. If this applies to you, play through the story series All Today Is Yesterday’s Tomorrow. The third task, A Moment of Peace, requires meeting Himeko and Asta at the Master Control Zone. Upon completion, Dr. Ratio’s email will be sent immediately.

Party Role and Team

Dr. Ratio can be excellent on certain teams, but only for some combinations. He is a single-target attacker, making him great for main DPS and sub-DPS roles. Dr. Ratio excels in a team with a well-built Topaz in Honkai: Star Rail. However, she is from various random banners and is not a guaranteed pull, making it hard to plan a team with her inclusion. Other recent new characters like Hanya and Argenti can also work well with Dr. Ratio.

It is best to rely on free and unlocked characters in Honkai Star Rail. Asta, March 7th, Yukong, and Serval are all suitable stand-ins while you seek out a stronger team. Making a perfect Dr. Ratio team may cost time and real money.

Regardless of the team’s makeup, Dr. Ratio mostly wants to make use of his Talent and Ultimate skill. This can cause heavy damage to even some of the strongest bosses in Honkai Star Rail. Dr. Ratio's Talent is Cogito, Ergo Sum, which has a 40% chance to deal follow-up Imaginary damage; and for each debuff the target has, this raises the chance by an additional 20%. Dr. Ratio's Ultimate, Syllogistic Paradox, deals Imaginary damage, and when an ally hits the same target Dr. Ratio will automatically use Cogito, Ergo Sum.