How to animate/simulate RUNNING

I'm trying to make a ninja game that utilizes running but how do I animate steps? How many different images should I use? As well, what are some events to simulate running, punching, and kicking?

Thanks to everyone

You need to Set the animation according to a key pressed - LINK

Dunno there's no premade formula for animation. It depends on the pace and style of your game.

• First make a prototype without animation to have a good feeling of pacing. In short, make it fun with only rectangles.
• And then try attaching some animated sprite to your rectangle and set it to be invisible. Then you can test some timing with roughly sketched key poses and some in-between maybe.
• Once your are satisfied, make the finished/polished final animations (: