A game of tag, on the other hand, often proves to be fatal.

Predator Cartoon

I had never drawn a predator before so I went looking for some reference images online and it occurred to me that predators have no nostrils.

Theoretically I've postulated that they're probably like alligators in that it takes very little pressure to keep their jaws closed as most of their muscles are geared towards having a powerful bite. So if you can keep a Predator's jaw shut for a minute or so he'll be unable to breath and fall unconscious as he has no nostrils to get more oxygen once his jaw is closed.

This is, of course, just a theory and you should consult with your doctor before taking on any aliens in head on battle.