For example the new grimoire needs to kill enemies in order to proc its bonus. Trumna needs to kill enemies to get alt-fire charges. You need to land the killing blow to proc Merciless.
For those who don't know, the Wyrd Scythes+Doom combo places a mark on enemies that gathers/stores damage for a few seconds and when that damage exceeds the enemy's remaining HP, it triggers and kills them with true damage.
If you're playing Dagath and using your doom abilities, are you inadvertently kill-stealing and making it impossible for your allies to complete these on-kill challenges? Or for that matter even for yourself?
It really doesn't matter, as doom's range really isn't that large and wyrd scythes has to kill the enemy to spread the doom effect, which just doesn't happen above level 100, even with a lot of strength. So it really just boosts the damage on the enemies right in front of you...
Wyrd Scythes only have to damage the doomed enemy in order to spread it, and it's pretty easy to maintain it once you get it going.
While the enemy has the Phantom Wrath effect active, it stores 35% of any damage Dagath does (whether ability or weapon) and then when the time expires, or the stored damage becomes lethal to the target, it triggers and deals that stored damage.
This means that for example if I store 50k damage on an enemy, and someone else's grimoire starts damaging the enemy and brings it below 50k HP, dagath gets the kill - if I am reading this correctly.
Then both my ingame experience, and the wiki that says
Strike Doomed foes with Wyrd Scythes to trigger Phantom Wrath, while refreshing Doom on the targets hit and spreading the curse to other enemies within a AbilityRangeBuff10 / 12 / 13 / 15 meter radius around the Doomed foes.
are wrong I guess. I can't test it rn but will later, but it doesn't really change the original point that much, just makes it harder to apply if true but not impossible since it isn't that hard to press 2+1 on a group of enemies
edit: Played a bunch with her and the doom effect definitely spreads on hit, not on kill.