New Doom blast

Imagine we have Despair + (new) Impending Doom Support + Spell Echo.

1. Will this combo cause Doom Blast immediately?
2. Will Doom Blast benefit from Despair?

How has Mark_GGG in friends - please call him for answers)

It should work like that yeah for clearing at least, though curses are really fast to cast anyway I don't think spell echo would be necessary you'd likely want another support

Spell echo is for better understanding the situation of a fast recasting a curse.

I tested in Standard, Doom Blast is not triggered when re-applying the same curse, so spell echo is useless. However, if you apply a different curse to replace the one supported by Impending Doom, then Doom Blast is triggered.

And yes, the blast benefits from the hex that triggered it. It's documented in the wiki.

I think you may look at Vixen's Entrapment for "fast application of curses".

Personally, I'm thinking on a 6L Curse A with Impending Doom used as a main damager, and a Vixen with Curse B and Curse C in it. By only using Vixen, your max Curse limit is raised to 2, and when casting your curse A, curse B and C are triggered (not casted) at the same time. This means it will end applying Curse A, then B and C pretty much istantaneously - since my curse limit is 3, Curse C will cancel Curse A (since Curse A has less remaining duration, even if it's just some microseconds away from B-C) - therefore triggering Impending Doom while still retaining the full power of 3 Curses on the enemy (Apparently Vixen hasn't been touched by the generic "non-self cast curse nerf" from Manifesto, mostly because in order to use Vixen you still have to self-cast a Hex anyway)

Tricks for this kind of combo:
* Impending Doom has a 0.15 Cooldown, while Vixen has a 0.25 cooldown for the curse triggering, so care must be taken with the right amount of cast speed. (0.3? Base cast speed would be 0.43 just because of Vixen's bonus on Cast Speed with Curse skill, so unless I can find some Reduced Cast Speed I can't have a 0.5 cast speed. Not to mention 0.5 is damn slow nowadays)
* While the combo was there since many league, never could have been tested because, well, Doom from Curse A would be basically 0 unless you got lucky with the "chance for curse to get Max Doom when casted".
* I think Spamming the curse in boss battles will miss 1 Impending every 4 casts, so DPS will have a hiccup from time to time (may want to use an utility Unleash Hexblast in order to clean up all curses from an enemy)

Another alternative may be using the new Cursing Ground support for one single self-cast Curse with Impending Doom - an enemy leaving the Cursed Ground will lose the curse, therefore triggering Impending - but it depends whether Impending considers the Cursing Ground as "triggered"