Ashen Grip is part of the base game. Crafting stations can be found in Glenumbra (Par Molag), Auridon (Beacon Falls) and Stonefalls (Magmaflow Overlook). You can craft any armor, weapon or jewelry with this set in any motif style you know, as long as you have 2 traits researched (per item). You can trade crafted pieces to other players. Each set item becomes bound on equip.