I realised that awhile ago CrownofFire, but it is indeed awesome. Of course there are problems when you throw in the extra one element several cultures have had, the two biggest being Lightning, which is more commonly consitered a Plasma than fire, and Soul/Spirt, which is hard to discribe.
I've never heard of Lightning being an element, would you be so kind as to point me to what cultures have it as an element? Spirit is generally considered a more abstract element anyway, from what I've seen. It's not really regarded as part of the actual physical world (which is why it's called Spirit ). But yeah, Spirit is generally purely non-physical.
Lightning, in my experience was considered the province of air, or in some cases the mating of air and fire but I've never seen it as an element itself, aside from in games.
Lightning/energy is an interesting element/force of nature if you look at it closely enough.
It utilizes a bunch of energy to be visible, but during a lightning storm when it's especially visible in larger magnitudes, it seems to exert so much energy, that when you watch it flash (IE- in a single discharge), you can sometimes see it fade in particles. My thoughts about that is essentially, if you look closely enough at the elements in action during a storm, lightning is a bunch of energy vaporizing tons of water molecules into their separate elements (Oxygen, Hydrogen, and Nitrogen), and then detonating the separate particles simultaneously (in a flash, so to say, except the nitrogen I think), resulting in tons of tiny explosions, stacking together into one really loud shockwave, thereby generating the thunder you hear after the flash. Simply put, lightning in storms are the tallest explosions you'll see one time or another up close.
The nitrogen being involved, I think, is already in the atmosphere, and the shockwave from the thunder forces it back into the ground fertilizing plants that are caught in the storm. At least, that's something I recall from some agriculture classes or something. Anyway, it is interesting to see plants look a whole lot greener after lightning has been striking closely after a storm passes.
EDIT:
Of course, this is just my observation and what I can recall. It's not perfect. Plus, it's been a good while since I took a class in the field.