Oh yeah, i just thought of something. Heat, (from fire) would harden sand, not only making Croc's ability useless, but possibly making him immoblie.
Or Smoker could at least cover the whole area with smoke making it almost impossible to see, oh, but that would effect the marines as well. Hmmm…
Hmm… Well it doesnt harden sand i think it turns into glass but i dont think ace's powers aren't as hot as that admiral with the volcano power. Anyways Nah i was thinking smoker, would cover the whole sea with smoke, (whitebeard might sneakup and kill everyone but its worth a shot) and then aokiji freezes it, valcano guy shoots it and the pieces crack... That would be the end of one piece but smoker wasn't thinking. I mean one of the rarest are logias and smoker wasting his in a small town isnt cool. Remember when they fought in logue town i think, it was a match