Actual player using doombot-like Lux abilities

In an ARAM game just a little while ago I encountered a player playing as Lux. Though for the better part of the game her abilities were acting normally. Then the last five minutes of the game came along and she had time to ult two times before their team won. On the first cast, the ability went off twice (or at least I saw it go off twice and so did my team, it may have gone off three times as in the second occurrence), once directly where she was facing and once again angled just to the right. On the second cast (it had time to come off cool down) it went off three times, one where she was facing, again to the side, and once behind her. I don't have a screenshot or know how to reproduce the bug exactly, but if I had to guess it's a protobelt bug, as the pattern seems to mimic the firebolt ability. I wasn't the only one that saw it and it's not just an animation bug, each instance of the ability going off per cast did damage.