Rotharran Radhelm is located in Feerrott, the Dream and sells Group gear in exchange for the following Alternate Currency:
This vendor has items that are locked behind the Dream Delvers faction as well as HoT Group Progression:
Apprehensive unlocks Tier 1 Gear (of Fearful Reverie).
Indifferent unlocks Rk. 1 Spells.
Indifferent + Tier 1 Progression unlocks Sparkling Fragment and Tier 2 Gear (of the Vagarious Servant).
Amiable + Tier 1 & Tier 2 Progression unlocks Shining Fragment and Tier 3 Gear (of Disturbing Visions).
Kindly + Tier 1, Tier 2, & Tier 3 Progression unlocks Emblems, Brilliant Fragment, and Tier 4 Gear (of the Elusive Eidolon).