I kept forgetting to do this, anyway, so there's actually a few examples in here. I threw this together in about an hour or two.
Hitting the gel monster does 20 damage, the spikes do 40 and the saw does 60.
Having no armor means you will die fast touching any enemy.
Wood armor protects x3, Silver protects x5, and Diamond protects x10.
I was going to do an advanced math example for stacking things like gloves and helmets, but I forgot how I was going to do it. You could just have an expression for A+B if you wanted to stack a x5 with a x3 and get x8 protection. That would work. I just didn't do it.
So, the other examples are recharge heart, saw sound distance, squash bounce, and damage knockback.
Click on any armor you want to try on and charge into danger to see how long you last against the damage.
I did some mild custom spriting and effects. I always like my small games and examples to look nice, even if they're a tutorial.http://flowlab.io/game/play/746950