Recording Crystals
Chisk doesn't know that his brother is trying to contact him, because Sam and the team tried their best to stop every single messenger that wanted to approach Chisk and made them disappear. They killed some, they imprisoned some in the chessboard, but not a single message was passed to Chisk.
But after this week, Sam imitated the writing of Leader 2 and modified the scroll. He had to use some special tricks to change the message so that the scrolls would still have the spiritual imprint of the Leader 2.
Sam never expected that such a forgery would take such a long time.
Kiran disguised as one of the captured messengers and took the scroll to Chisk.
Inside the scroll, the original message was for Chisk to stop the madness and go back to Leader 2 instantly, but the current message is about praising Chisk for his contributions and telling him to expand the territory even more and even faster.