Incredible bug, instant Arcane Comet with Swain

Arcane Comet BUG
Firstly normal speed, then x0.5
I really can't describe what exactly happend, because i played Swain first time. That's why i put link with replay in my thread. In shortcut- URF- I killed {{champion:63}} by {{champion:50}} throwing **9 Arcane Comets in 3 seconds !!!** Maybe you know what happend, so don't hate me for no writing with this pattern _[HOW-TO] Report Bugs on the PBE_, but let's solve this bug together ! {{sticker:slayer-jinx-catface}}
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