Su Yu's decision to livestream the assault on Spiritual Spring Eye wasn't impulsive, but premeditated and discussed with Snow Leopard.
Given the unusual circumstances, the video of "Assaulting the Spiritual Spring Eye" would be uploaded online right away for everyone to watch and study.
Since the video was going to be shared immediately, why not show it directly to everyone via live stream?
Moreover, during the live stream he could interact with everyone, answering some detailed questions that Su Yu might have overlooked but some people still didn't understand.
As for the gory scenes that might appear in the live stream, such as "Skurus being torn to pieces by magic" or "Skurus dying miserable and bloody deaths", this isn't peacetime anymore. Everyone has to face these scenes sooner or later, and it is better to have some mental preparation in advance.
That's why this live stream was created.
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