Dark Knight

Overview
A basic melee enemy encountered primarily in Area 1. Deals physical damage.

Transform into Dark Redeemer (passive)
Requirements: Must have the Redeemer's Mark effect

Upon taking fatal damage, become immobile and damage immune for 2(?) seconds, transforming into a Dark Redeemer at the end of the duration.

Strategy
If you can, avoid their attacks if you have enough movement speed to do so, it is a lot easier for ranged heroes to take care of these units without getting hit than it is for melee heroes to do so.