84 articlesDr. Ratio is one of the newest characters to join Honkai: Star Rail’s ever-increasing roster, and you can get him for free currently.
You’ll have to act relatively quickly, as he will only be free until Update 2.1 releases. That said, Update 2.1 is probably at least a couple of months away from release, so you’ve got time.
Nonetheless, we’ll tell you everything you need to know to claim your free Dr. Ratio!
Claim Your Own Free Dr. Ratio Now!
Dr. Ratio is free to claim starting with the “Panta Rhei” Character Event Warp from January 17, 2024. He will be available until the release of Update 2.1, which has yet to receive an official date.
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Enter Black Cat Instacam’s Delusional Theater Once in Honkai Star RailFeb 16, 2026The only prerequisites are that you need to complete the “The Blue — A Moment of Peace” sub-mission and have unlocked your mailbox.
“The Blue — A Moment of Peace” is the third part of the “Today Is Yesterday’s Tomorrow” Trailblaze Mission. It’s the first Trailblaze Mission during the game’s Prologue chapter!
So, basically, you just need to progress through the game’s tutorial until you get access to the mailbox.
Once that’s done, open the in-game menu and look for the Mailbox. It’s denoted by a letter-shaped icon, you can find it on the rightmost side of the screen.
Then, look for an e-mail titled “Subscription Reply from Dr. Ratio.” Open it and read its contents if you want, then click on the “Claim” button in the bottom right corner.
You’ll instantly receive Dr. Ratio into your roster, no strings attached! You’re now free to add this powerful Imaginary-element character to your party whenever you wish.
If you have no idea how to play Dr. Ratio or how to build him, feel free to peruse our Dr. Ratio build guide.
It tells you everything you need to know about him. It has everything such as what his playstyle is, what equipment to use on him, and even which characters make the best teammates!
Nonetheless, we’re sure this powerful unit will help you as you explore the galaxy and blaze your own trail.
ALSO READ: How to Unlock Items in Honkai Star Rail
