(3) Set: Increases damage and healing done by magical spells and effects by up to 28.
(4) Set: Chance on landing a damaging spell to deal 75-85 Arcane damage and increase the target's Arcane damage taken by 10 for 15 sec. This stacks up to 3 times.
Stat calculator
Uncheck pieces you don't have to see the set bonus without them.