[GAMEPLAY] Mordekaiser Q intermittently does not apply his auto attack damage

Mordekaiser's Q empowers his next three auto attacks with bonus magic damage. However, when auto attacking a target while Q empowered, it does not always apply his basic attack damage.

This isn't just a difference between an enemy getting off on 1 HP: Mordekaiser has the highest AD scaling in the game, to miss out on this physical damage when he auto attacks using empowered Q can cause him to miss out on a huge portion of his damage.

Not applying the basic attack damage once in the linked GIF, at level 12, Mordekaiser missed out on 111 physical damage, if this occurred on all 3 Q procs, then he would miss out on 333 damage, which massively impedes his damage throughout the game but more so in the laning phase when trading.

Please note I have calculated the damage dealt to targets when the auto attack damage isn't applied on the tool-tip (popup text) to make sure this wasn't a visual issue.

The bug occurs essentially every Q cast, on at least one proc, but can sometimes be on all three. I cannot imagine something this random being intentional, it is easily reproducible, simply use Q as Mordekaiser and auto attack any opponent and watch to see if it applies his auto attack damage.