There's few conditions that have to be meet for a successful interruption:

1st. Was opponent casting from position in team that was making it possible for your interrupter to success? aka- never try to interrupt position 1 ninja from your position 2 or even 3 (saw some magicians trying to do this).

2nd. Ninja which is trying to cast mystery might have immunity for interruption with that certain skill. Keep that in mind.

3rd. Going back to positions- even if your ninja is on same position- you still need higher initiative and/or good reflexes to succeed.

4th. Connection might still be a thing- either your or your opponent's.

Generally speaking, I face much less problems with all kind of delays after the introduction of 5.0 so maybe it's worth to look a bit deeper on the situation- maybe problem lays somewhere else, not in game itself.

1. It happens when my pos 2 ninja tries to interrupt pos 3 or 4.

2. No, i'm sure the ninja I try to interrupt are not immune to interruption. It happens all the time with all sorts of ninja.

3. The issue is not just with equal position, but also lower position casting skill before me.

4. Could be, but I honestly doubt it. My connection is usually good and the game doesn't lag. It also happens almost all the time, so it has to mean that all my opponents have crappy connection? Don't think so.

I forgot to mention that I notice this happening mostly in arena and Matsuri. Not sure if it happens elsewhere or not, since i haven't paid attention. Have to check this out in tomorrow's sage.

Edit: so i tried interruptions with a friend. He used Iruka on pos 1, and with Iruka he could not interrupt my main (pos 2) or Kurenai (pos 4). However, he could interrupt Jinpachi on pos 3... Now what's going on here? Of course, i couldn't interrupt his main who was on pos 4 either. The mystery sign above his main's head appeared half a second before the mystery was cast, so I didn't have time to click my mystery.

Up

The problem still continues.

keep in mind that if the control of your unit is less than the opponents unit, you will not be able to interrupt it

The problem here is that I can't even hit them before they use mystery.

well you need quick reflexes and a good timing... Personally i don't have a problem when interrupting a mystery, only when i have to interrupt mains... Cause if you try to interrupt them during shiba summoning or katsuyu's healing, their mystery goes first anyway and you go after it...

Thank you! So I'm not the only one having trouble interrupting annoying wind mains.

But it is not only the mains. Have you tried interrupting ninja like GNW Tenten, Gaara, Kurenai, and any other ninja whose mystery does not give extra standard, shield, chakra or clear debuff? Because those literately don't give you enough time to even click your mystery...

Ninja like Jinpachi, Sage Naruto, and water main with experimental ninjutsu (if they use mystery before their standard) are slower because they clear debuffs, give standard or chakra etc before casting mystery, so interrupting is possible.

i agree it's hard to interrupt mysteries. personally i don't think it's a bug, but more of my slow reflexes. who knows, maybe oasis might make it easier to interrupt skills XD

i think it all depends on timing... if the opponent activates the mystery while someone is doing their move you have a chance to see them infusing chakra and you can stop them... But if their timing is perfect either you have to predict when they will use it or you just can't stop them

This.

Interruption needs great timing- even if your Iruka is on position 1- and opponent tries to cast from position 3- if you won't do that in right moment, you may fail it. It's like a one second difference sometimes which determinate if you will be able to stop opponent- the second in which the game already proceed opponent skill.

Non-prompt skills are easier to interrupt- especially if opponent don't have a great timing with casting it.

And also this- interruption is nothing like some control statuses- for example immobilization. It don't leave any effect on opponent's ninja if you cast it earlier- so it's usually all about precision and reflex of caster.

It surprises me how many of you don't know this- or the amount of you that think this game takes "great reaction time".

It's not a bug, the game is turn based with wiggle room, everyone has a "Turn" each position takes their turn depending on their position & initiative- for some reason before the update there was a "Delay" before every action was committed, almost as if the game added it's own "breathing room delay"(Including queueing up a mystery), the only time this isn't the case is just before the standard attack of a Ninja, there seems to be a "Clear Opening" where it will instantly queue the mystery & activate it because "it's that ninjas turn", so for example Normal Gaara- if you used his mystery EXACTLY in the window just before his standard, he would instantly cast his barrier
(this is still the case btw, I've never had my Gaaras barrier cancelled by an interrupt, it's impossible. It's only possible in teamplay due to not being able to accurately account for everyone's turn)- not really a bug, more a symptom of the system in place.

That system still exists but all delays have been taken out, even the delay when you queue'd up a mystery, so much so that it has made even things like team play & GNW significantly faster- I think they've done it by not trying to sync the players together as heavily & probably just a cleaner construction on the back end- or maybe the game did deliberately add the "Delay" before every action.

This in turn is why you can't interrupt other peoples mystery as in most cases, assuming you don't use your mysteries exactly when another Ninja is taking an 'Action' such as during a chase, or even during the "Heal" animation on a healer, it will just instantly cast the mystery- you click it, it uses it assuming no one else is taking an action.

The only time I've found this not to be the case is against players with much lower ping, some times they are just ahead enough to instantly click & cancel an ability with an interrupt as if there's a delay on my end created due to latency but it's super rare & is only accounted for due to me playing on US servers when I'm in the UK.
Generally speaking though, no one on this earth can ever cancel one of my mysteries if I use it correctly- you don't have godly reaction time, you just can't beat how the game is set up mechanically.- The only time this isn't the case is if you know about this mechanic & know I will use Gaara just before his standard attack, in which case you're waiting for the same thing- using your mystery just before my standard.

The best time to use an interrupt is by trying to gauge when they will actively click it- A good example is with Water Main blitz, when Mabui takes an 'Action', for example the "Heal" on her turn, she gains chakra- if you wait for that "Heal" people generally instantly click Tenten as soon as they get that chakra, wait for Mabui's "Action" then use your mystery & they should queue up Tentens, of course people know this & just don't queue it, which is why the ninjas that interrupt aren't that great.
This is also an "If they're using Water Main blitz", generally you just can't anticipate when they'll use a mystery,