I forgot to mention that the most brilliant sign at the No Kings protest was simply the flag of the state of Virginia, which depicts a bare-breasted Amazon warrior standing with one foot triumphantly on the chest of a defeated king, whose crown has rolled to the side. Underneath are the words "Sic semper tyrannis" (Thus always to tyrants).
https://commons.m.wikimedia.org/wiki/File:Flag_of_Virginia.svg