Today, while playing Vi vs Lux, I used Vi's ulti on Lux so she used hers too and I noticed her ulti wasn't interrupted, so she was basically in the air casting her ulti while being punched.
It was pretty sad to see it.
Final Spark isn't a channel, so what's to interrupt?
Lux and Ez ult cannot be interrupted unless, I believe, they are killed. I'm pretty sure there are a few more skills like this as well.
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