Vi's E cone sometimes doesn't work at all or fires only on a few targets rather than all targets. Just use E on a large group of minions several times. It'll fail like 50% of the time, maybe based on position.
When it fails, it usually works for the close targets, but anything farther than 100 units receives no damage.
Additional info: I've seen people mention that some conic skillshots fire backwards. It may be the case here that the cone casts backwards but the animation/particle plays forwards.
I've actually seen this happen once during the making of the above video, but discarded it as an outlier.
I'll upload the clip in a minute
EDIT: https://www.youtube.com/watch?v=FIX8Kn4uOeQ
I'm like 80% sure now that this is what's happening.
Bug Confirmed
It seems to be a range issue. It feels like it's at about half of normal max range.
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