drained lake mud , like quicksand can be tricky if you don't know how to get out of it.
possibly even worse then quicksand.
mud works like a suction cup.
even an inch deep mud can grab your shoe and pull it right off as you walk.
I hear you can swim in quicksand.
if you get stuck in mud up to your Knees, Either immediately Sit down
or Rock Forward and try to stand on your Toes.
pop your heel loose.
then immediately turn around.
If you can't pop your Heels,
walk out of your Shoes/Boots.
I've never reached the waist level that I remember.
I knew what my Limits were .
but seen Kids & Women panic and need to be rescued from waist/hip level Mud.
of course of all things make sure you have a Phone on you , or other "Human" life within sight.