well, it's a 2 AP aoe spell which hits the largest circle aoe before arrow storm, has a guaranteed initial damage tick which does a lot of damage, seemingly far more than your regular weapon attack (which is what is used when someone actually does enter the aoe). it's already better than most skills you have access to at this point in the game
the "non-guaranteed chance for additional damage" comes (or should come) in the form of zoning off an aoe and discouraging enemies from entering it. currently though, its most effective use is simply dealing a lot of damage in an aoe, with the entry hazard effect functioning as more of an afterthought. this isn't what i imagine the creators intended when they created the skill
the issue to me seems to be that the skill was pretty bad beforehand, so it was buffed, but in the process of doing so something went wrong and it got overbuffed. on top of that, it seems like the intention behind the skill has been turned on its head
it also doesn't make any sense for it to hit allies. not even arrow storm does that