(In Game) Malzahar voidling "ghost"

Was playing lucian adc and on the enemy team was a malzahar. malzahar would summon a voidling and even after it died, it would still be there invisible and indestructible. Untill malz came back with another one summoned.

it did damage to me and minions targeted it. my champ would keep on attacking this (ghost?) voidling untill malz came back up, i could walk away but it would follow