Knightmare is a heavy armor set. When you deal melee damage, you have a 20% chance to apply Minor Maim to all enemies within 8 meters of you for 5 seconds, reducing their damage done by 15%.
The Knightmare set is part of the base game. It drops in Spindleclutch I and Spindleclutch II in Glenumbra. Each set item is bound on pickup. You can acquire heavy armor, weapons and jewelry of this set in the Wood Elf motif style.