| Easy caster legendary proc. Make the stats similar to the Staff of Ruins from AQ20 - not overpowered, just decent. Like Thunderfury.
Chance on Hit: Causes the target to be vulnerable to magic, increasing magic damage and effects against this target by up to 25. Lasts 20 seconds. Stacks 5 times.
Make it a 30-40% proc, and bam - caster legendary that does something no other weapon can - ends up being a shitload of damage and benefits the whole raid, just like thunderfury. Tweak the numbers as desired. | 