There should be a separate rule that does not allow kings to capture.
Yeah but then king-pawn endgames would get very boring
https://www.chess.com/clubs/forum/view/variants-server-suggestions-post-4pc-merge
You can turn it off.
My suggestion was for NCVs and WoFs.
We don't have that rule for now, but maybe using Atomic, fatal capture, or racing kings, you can make something similar?
I intended for it to be added in the future, after all the connection issues are fixed.
There should be a separate rule that does not allow kings to capture.