Was there a specific statement that Kashimo’s Mythical Beast Amber was suicidal, or is it just the most likely conclusion to the statement that it can only be used once?

Just curious if it was ever stated by Gege or somewhere in the manga I missed. It’s probably just a suicidal attack, and Kashimo had a basic understanding of how it worked from his time in the Edo Era.

I just find it weird that if he had never used it that he would instinctively known how to use it/what it did. Sort of like how Satoru Gojo understood Limitless from the beginning, but only really knew about Purple due to secrets and discovery within the Gojo clan.