Currently shadow priest is too single-target oriented with little to no emphasis on dot dmg in most scenarios (PvP and PvE), so we could get a legendary that increases Vampiric Touch and Shadow Word: Pain by let’s say, 3% for every second spent in voidform. That would make us play around voidform and not around some random pet and Power Infusion. This is considering the chance of double legendary in 9.2, having something like this would make dotting feel like it should be again.
Kind of like the old Mass Hysteria artifact trait. I like it.