varus blight in one-for-all

was seeing those damn 5-man tahm teams for the event stacking his passive and spamming devour and got curious on how W Blighted Quiver would work with it since the blight damage varies greatly depending on if ap or ad.

Let's say AD varus stacks 3 stacks on some poor unlucky enemy champ Then a high AP varus procs the stacks with a skill.

do the stacks do the blighted damage from the AD varus or the AP varus?