Mordekaiser 0 damage to minions

I can't really replicate the bug, but if you play a couple of games on him it should occur at least once or twice.

I've had it where both Q, W, E fail to damage minions.

Q seems to occur right after you activate E, or reactivate W. Where W/E will sometimes just not damage minions within their AoE.

If i were to guess, it seems to be something to do with animation canceling, but again I'm having a hard time reproducing the bug. I've yet to have it occur on champions, but it might be possible.