No seriously, someone check the math. I don't think there's any other ability, Ultimate or not, that's capable of dealing the same amount of damage, but I'd not be surprised if I'm forgetting something.
SO I guess the obvious question is HOW?
Put simply , a combination of things adding up.
First, we start "Base" Combust.
Pretty straight forward. 5 hits of 20%-37% damage over 6 seconds for a total of 100-188% of active spell damage, which doubles to 200%-376% if the target moves. A good solid ability.
Next, lets add Exsanguinate, or rather Wrack & Ruin for an extra 2 hits.
7 hits of 20%-37% damage over 6 seconds for a total of 140%-228%, which doubles to 280%-456% if the target moves.
THEN we add Lunging into the mix.
7 hits of 36% - 67% damage over 6 seconds for a total of 252% - 469% which increase by a further 50% to 378% - 704% if the target moves.
FINALLY We get a flat 25% damage boost to Combust from out newest addition, Kerapac's wrist wraps, "Whilst worn, for six seconds after using the Dragonbreath ability, the Combust ability will deal 25% more damage - and deal it instantly."
This means in the end, we have an ability that does 7 hits of 45% - 84% damage, or 315% - 588% damage instantly, increased further to 473% - 882% damage if the target moves.
Duuuuuuude, Someone tell me if my Math is right, or if I'm totally wrong here.
Honestly, It sounds like I might be wrong, because that's Crazy for a Basic ability.
Since the damage is dealing instantly, how will it matter if the target moves or not? Am I now missing something or did I capture it correctly? Combust if hit instantly, will not double as the wrist wraps will make it just a single hit ability, hence making movement of target irrelevant.
Remember, we have only seen the first of four fronts of the EGW. There are going to be plenty of new items/spells/code/buffs etc coming out soon. I have a feeling we will see better spells as usually the BiS stuff comes at or near the end of the expansion.
Even for now, AOE spells like corruption blast/shot still deal far more DPS, especially when the target moves and corrupts more on its way. What if we see Greater Corruption Blast next? WoW!!!