(2 items) Adds 1096 Maximum Magicka
(3 items) Adds 129 Spell Damage
(4 items) Adds 1096 Maximum Magicka
(5 items) Whenever you deal Flame, Shock, or Frost Damage, you gain 492 Spell Damage for that element for 4 seconds. Each effect can occur every 4 seconds, and multiple effects can be active at once.
The Elemental Succession set is part of the Orsinium DLC and can be found in the Maelstrom Arena in Wrothgar. Each set item is bound on pickup. You can acquire light armor, weapons and jewelry of this set in the Malacath motif style.