My Suggestion:
New Item- Spell-caster’s Edge
Upgrade from Glimmer cape and Phylactery- thus all glimmer cape effects applies.
Recipe - Glimmer Cape + Phylactery + 250g recipe
New - Break - the first single target spell casted while turning invisible will deal an additional 200 bonus magic damage, slow by 15% and disable the targets passive abilities for 2.5 seconds.
I always thought phylactery is a weird item but this upgrade will make it much more appealing buy for supports imo while not making a super broken item and also keep with the theme of break items being tied to invisibility.
Void had two passives.