i unfortunately have been forced to look at kali , with a string of garlic around my neck and a crucifx in hand , i might add due to some tools for slackware current being a problem do to OS in constant movement.
i used this command to do it :
# dd if=kali-linux-2020.1b-live-amd64.iso of=/dev/sdc
where /dev/sdc is a none mounted usb stick
i can do anything using : sudo <command>
docs say root user creds are :
well that didn't work
theres 2 commands adduser, useradd
I can never remember which was is easy and which is a pain in the butt.By why bother with another user?
Also basically all you need to remember is that kali is Debian based so most
of Debian approaches to doing things should work on Kali.
Ps on splash for boot up it did give a choice of "persistence" i didn't have the patience to test that out though