Weeeeell, I could be greeeeeeeedy and say "all of them" (

to all of you who said "all"!), but I think water would be pretty incredible. After all, it trumps almost everything but air. Think about it...water turns earth to mud and kills fire. Only air can churn up the water (look at what a pretty good storm can do to any large body of water). Heh heh. But each has its merits:
- fire trumps air (real fire EATS air...well, oxygen anyway, for fuel)
- earth trumps fire and air (without wood, fire cannot spread across the ground, as dirt itself isn't flammable (and earth thrown on fire can put it out), and it can stop air
- water, as I said, kills fire, and turns earth to mud
- air can stir up water, and can also trump fire (if strong enough)
Hmm...fire is pretty destructive, but it looks to me like, pound-for-pound, it is one of the weakest elements when faced with the others! LOL!