Another thing that hurts a lot is having the air sucked out of your lungs forcefully, you just need to close the nose and go mouth-to-mouth and suck the air out, even if they try it's very hard to close the larynx because it opens outwards (the glotis that is) and the only way to really force it shut is by swallowing but you can also avoid that by using your tounge to tangle theirs. It feels really good but is very dangerous as you can also collapse the lungs if you suck out too much air and die.