Like the examples you used. We've gotten too used to the spine ripping, so we don't notice the strength needed to do something like that. Say what you will for the AvP movie, but that scene was an awesome show of strength (even though it was a bit degrading for the Alien, but the Alien did get it's revenge, so I don't mind). The comic panel of the first AvP when the Predator forcibly opens a metal door like that is also a crazy thing. Loved the scene where in Pray, the Predator lifts the bear slowly. Those are all great ways to convey the strength of the character.