Why do I still get put to sleep if I have the black shield up even if I shielded myself half a second before the sleep kicks in?
You could say It still technically hit me before i was protected by the shield, but shouldn't the fact that I have it on negate it the sleep?
If that's the case, why does black shield stop Nautilus's ult or Vi's knockup on her ult while they're channeling towards the target? Since they were cast before the shield was on them?
Black sheild does NOT cleanse.... you are already hit by the spell so it remains in effect.
I'm guessing it's because Zoe's sleep is a delayed effect. Once it hits it has a "cast time" and will put you to sleep accordingly.
A different example of ability interations would be tethers and untargetability. Morgana Ult is still attached to Vlad when he pools or when Fizz uses Troll Pole. Of course not the same thing but the same concept.
The example of Vi is different because its a physical knock-up and not a spell effect.
Or even better example is if Malzahar had 
and puts his DOT on you and you spell shield afterwards, you will still be slowed. Zoe's spell is still in effect because it was applied before Black Shield, the sleep portion is just delayed.
Because certainlyT is a terrible person and was like "MUH STUFF HAS TO BE BROKEN!!!" So riot allowed it.
it really should prevent the sleep to be consistent with how ti works with other stuff
i dont like revealing secrets i like to abuse but basically blackshield has a secret interaction with zoes E... so say zoe Es you and you black shield right when sleeps about to go off it doesnt work.... but say you blackshield before E hits you... you wont be put to sleep basically meaning you have to block the initial spell hit
I'm pretty sure it's because Zoe's E is a new CC ability that puts enemies to "sleep." So basically, the specific code hasn't been properly integrated into every part of the game... so there's quite a few bugs with Zoe's Sleep and some other champions and items. There were other complaints about it on the boards already.
I think it stops Ornn during his unstoppable ability. I believe Mikael's Crucible doesn't cleanse Zoe's sleep. I'm not even sure if the summoner spell Cleanse works on Zoe's E. Zoe's Sleep might even stop Sion's Unstoppable Ultimate. Not sure though.
I ran into this yesterday. Regardless of when the ability hit. Black Shield should prevent the CC. This applies to Vi, Naut, Hec, etc... Black Shield should prevent any cc applied while its active regardless of cast order.
