3D Character Animation Video references

Here are some videos I found for my 3D Animation class which I will use as a reference to hopefully portray a sneak attack on an unsuspecting guard or something. Kind of Rambo or stalking type of action. Here is a video of Solid Snake from the game Metal Gear Solid 4: Guns of the Patriots.

http://www.youtube.com/watch?v=7H6f5sABarI

This second video is of Rambo beheading someone. I am planning on using this video just for camera reference for my final render.

http://www.youtube.com/watch?v=hpC_A-KbaOQ

This is the kind of sneaky walk I want to do but with a bit more character and pause in action as If he is stalking someone. I am planning on adding a character to which he attacks but If not, I want to make sure the walk looks believable.