In an interview with Famitsu, Dark Souls and Elden Ring Director Hidetaka Miyazaki confirmed that Radahn must be defeated in order to access the Shadow of the Erdtree DLC.
It seems safe to speculate that this must be because of Radahn's conquery of the stars that left fate itself held in stasis.

However, did you ever stop to think about why Radahn did this? Did he really just want to stop Ranni for some reason?...And what exactly does it mean to conquer the stars anyway?

In this video, we explore a new theory that seeks to explain Radahn's true motivation for fighting the stars. Spoiler alert: it's pretty badass.

I'm still riding on the wave of the hype of the story trailer so I tried to channel it into something cinematic for you guys: hope you enjoy! :]

Thank you to BlaiddFailcam for letting me reference his excellent post on Reddit:

  / a_slightly_different_reading_of_radahns_co...  

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