Plagueheart Sandals

Plagueheart Sandals are shoes for warlocks. They are part of the Plagueheart Raiment armor set.

Source
The sandals are a quest reward from Plagueheart Sandals (quest), crafted by a vendor from Desecrated Sandals, an item which drops from Instructor Razuvious and Gothik the Harvester who currently reside in Naxxramas.