Color spray duration?

[smcmike]

Duration = one round. When does that end, before or after the caster's next turn? I don't see anything definitive in the books, but True Strike's text is interesting - up to one round and it is only usable the following turn.

[Lombra]

Color spray ends right before the turn of who casted it. True strike has the same duration but it is delayed so that the caster can benefit from it.

[Segev]

Honestly, color spray seems almost as bad as witch bolt, to me. The Blinded condition is nasty, but not as nasty as what sleep inflicts, and this lasts far less time. The higher hp that it can effect is a small boon, but it's not enough more to make that big of a difference, and it's still too little to be a good alpha-strike. With only one round duration, it is situationally useful (you have the drop on the enemy) and it doesn't even affect the most dangerous ones. Under most circumstances, you'll already have allies intermingled (risking blinding them) by the time you get to use it, and they won't be able to take advantage of it even if not, since it affects the weaklings first. And it's over in one round.

Sleep is just significantly better, for the same slot. Where it shares risks and weaknesses, it makes up for it in effectiveness.

I'm playing an Illusionist, and I don't have this spell, because it's so pathetic and hard to use. And it doesn't even synergize well with Illusionist class features.

[smcmike]

So it's generally agreed that it ends at the start of the caster's next turn?

And, yeah, it doesn't seem great. I'm asking this question because we are playing through LMoP, and our illusionist blinded some wolves, and wanted to know if his Witch Bolt the next round had advantage. So....