A dark knight has the following special benefits:

A dark knight can detect characters and monsters of good alignment when concentrating on doing so up to 60 feet away.

A dark knight receives a +2 bonus to all saving throws.

A dark knight can transfer any disease he has to another, thereby absolving himself of the disease.

A dark knight can draw life force by laying on hands. He will absorb 1 HP per experience level, unless the victim saves versus spell, in which case, he only absorbs 1 HP per every two experience levels. This can be done only once per day.

A dark knight can afflict a person with blindness for 1D4 + 4 rounds, silence for 1D4 + 4 rounds, weakness nullifying the target's Str bonuses to attack and damage rolls until the target sleeps, stiffness nullifying all Dex bonuses until the target sleeps, or forgetfulness which will cause a priest or mage to forget 1D8 of his memorized spells for the day. This can be done within 20 feet and can only be done once per week per every five levels of experience.

A dark knight is surrounded by an aura of protection with a 10-foot radius. Within this radius, all summoned and specifically good creatures suffer a -1 penalty to their attack rolls, regardless of who they attack. Creatures affected by this aura can spot its source easily, even if the dark knight is disguised. The auras of protection of paladins and dark knights are mutually exclusive.

A dark knight using a dark sword projects a circle of power 10 feet in diameter when the sword is unsheathed and held. This power dispels healing, restorative, and reverse necromantic magic of a level up to the dark knight's experience level.

A dark knight gains the power to command undead when he reaches 3rd level. Use rules for a paladin turning undead; all the turned undead fall under the command of the dark knight and obey him unquestioningly.

A dark knight may call for his war horse upon reaching 4th level, or anytime thereafter.

A dark knight can cast priest spells once he reaches 9th level. He can only cast spells of the combat, divination, necromantic, and protective spheres. A dark knight uses the same spell progression as a paladin.

A dark knight has the following disadvantages:

A dark knight's dark powers feed upon his own life force. He must draw 5 HP of life force from living beings per week or temporarily lose one point of Con per week until he makes it up.

A dark knight's dark powers interfere with healing magic and potions. Any healing magic or potion used on the knight will be half as effective, rounded down.

A dark knight radiates an evil aura within a radius of 10 feet which makes people feel chilled and makes creatures of animal intelligence or lower fear attack, causing them to respond accordingly.

A dark knight does not attract a body of followers upon reaching 9th level or building a castle.

A dark knight can hire only evil or chaotic neutral henchmen.

The Dark Sword item is included here as well.

Sword, +5 Dark Sword: In the hands of any character other than a dark knight, this sword will perform only as a sword +2. In the hands of a dark knight, however, it creates magic resistance of 50% in a 5-foot radius, dispels magic in a 5-foot radius at the level of the dark knight, inflicts +10 points of bonus damage against lawful good opponents, and restores HP to the dark knight equal to one-half of the damage inflicted, rounded down. The dark sword will never inflict more than 1 point of damage per hit against undead or magical evil creatures.

If a holy avenger and a dark sword are within 10 feet of each other, then regardless of who wields them, they function only as swords +2 and all special abilities are nullified.