Black Knight

He is a member of the TBI who turned the other way. "Commander of the Royal Army, assumed dead in the collapse of his unfinished home." Spawn cannot be blocked.

The Black Knight fights with Melee and throws Spears when the enemy tries to escape. A Black Knight never retreats.

For Druids and Sorcerers this is a very hard creature to hunt, forget your Icicle and your Stalagmite runes here, since he is immune to Earth and Ice Damage. Since he's resistant to all other elements, the best you can do is to use Explosions or Physical Strikes.

A basic strategy consists of the Knight blocking the Black Knight and Challenges it whenever it retargets, while the Druid/Sorcerer uses the above. But the most efficient duo-strategy to kill it faster would be a Knight blocking while a Paladin uses Divine Missiles. Not a good creature to do a fast hunt on since he takes quite some time to respawn (around 10 minutes with regards to the server state). It is possible for a Paladin to solo this creature at level 50. It is reccomended that you take either Royal Spears or Enchanted Spears and a good shield, though you should kill the Bonelords first to avoid mana drain. If you can, also kill the Scorpions too. This will dramatically increase your chances of succeeding.

Although the sprites for black knight were implemented on Update 5.0, its spawn was probably added to the game with Update 6.2 when Green Claw Swamp was revamped.