Board Thread:Questions and Answers/@comment-14.231.236.178-20170909050646/@comment-25669516-20170909093557

You need the entire set only to unlock Tempest Rage. After that you can switch individual equipment out for something else, provided the new equipment piece also has Tempest Rage enchantment. Anyway, the armor and helm are purely cosmetic. It is the weapon, ranged weapon amd magic that you need to pick according to your playstyle.

Frankly, in the end, you can use anything if you are willing to be patient and don't mind retrying hain and again. My gear while defeating May and Titan was Damage Absorption on Monk's Armor and Helm, Poisoning on Monk's Amulet, Frenzy on Katars and Overheat on Shuriken. Not that strong a combo but I did manage to defeat them both in normal mode and in Eclipse.