Indomitable Fury is an Rewards for the Worthy Set. Set pieces are also awarded via "Rewards for the Worthy" mails by participating in PvP. Pieces are Aldmeri Dominion, Daggerfall Covenant, or Ebonheart Pact Style in Light Armor.
2 items: Adds 25-1096 Maximum Magicka
3 items: Adds 25-1096 Maximum Magicka
4 items: Adds 3-129 Stamina Recovery
5 items: After Breaking Free, you gain Minor Protection and Minor Heroism for 7 seconds, reducing your damage taken by 5% and generating 1 Ultimate every 1.5 seconds.
The set consists of light armor and jewelry in all slots, as well as weapons and shields of all types.