Fist of havoc also has a higher energy cost per use, it's ground limited, and does lower damage per aoe to where damage fall off has a bigger impact. Fist of havoc also doesn't have any way to heal itself like nova warp does and has a lower roaming duration. This isn't me saying that nova warp is better because it's not (exclusively because it has no light attack that doesn't suck), but rather that nova warp shouldn't just BE fist of havoc. Dawnblade is what happens when you take base hammers, give it more maneuverability, a longer duration, and more swings. This is essentially what nova warp is, only it severely lacks a quick way to kill and is one of and the biggest flaw it has. Cause fist of havocs aoe is pretty much just for the cast and then you mash rb because it's way more reliable.