Collei, a new playable character, is revealed upon entering Genshin Impacts Sumeru region, where she previously escaped. During her escape, she befriended other members of the Fatui leadership named Il Dottore. In-game, Genshin Impact doesnt really explain Collei's story, mostly having Collei add color-commentary random phrases of dialogue.
It's likely that Hoyoverse released the manga for the first time two years prior to the official game. Chapters began dropping in 2018 and ended in 2020, and it can be seen on Webtoon, Tapas, or the Genshin Impact website.
The manga corrects this. Early-game characters gain some depth. Ventis reign as Archon is explored. Most importantly, the manga explores Amber's development as a hero.
The best time to read the manga was before Genshin Impact was released. The second-best time is right now.
The manga also lays the foundations for Sumeru. Colleis' entire backstory is explained. You'll also learn about Dottore's interactions with high-ranking Mondstadt characters like Diluc and Kaeya. Even Sumerus General Mahamatra, Cyno, briefly appears.
The manga has already been mentioned on several occasions, confirming it as a canon. Some Sumeru residents like Tighnari have in-game voice lines explicitly referring to manga events. Dottore is constantly being established as an imminently coming villain via hidden quests like The Bad Guy in Vimara Village and the trailer for patch 3.1. If you want to fully enjoy the game, the manga should be read.
The first 13 chapters of the manga can currently be read in English, although there are 16 chapters in total. At the time of writing, the last three chapters are only officially available in Japanese, Korean, and Simplified Chinese. Hoyoverse has yet to translate the final installments into English.
A few Twitter users aimed to translate the remaining chapters rather than allow the fandom to make assumptions from the summaries. Another user, DarkKnightHero, found AseriaSallarias translations and typeset the dialogue to the page.
AseriaSallaria told Polygon that the manga made me fall in love with these characters.
AseriaSallarias' translation of the final three chapters of Mangadex is currently available. For her, these chapters have added weight to Sumeru. I was eager to see Collei in-game, and it finally arrived two years later!
If you already like Genshin Impact or if you are a potential fan who wants to share the game with the world, do not let Hoyovers' lack of translation of the series' denouement stop you. The community surrounding the game worked together to ensure every fan has access to the story. Do not let the manga go by you.