Spectral Forms- The Dark Judges are not actually physical beings. They're spirits, which normally appear as smokey masses with their face in the middle. They can possess a ripe dead body and alter that body's appearance to match their own, which allows them to interact directly with the physical world and to more easily use their powers.
Immunity to Pain- Due to the fact that the nerves in their corpse bodies are dead, the Dark Judges cannot feel any pain. Thus, trying to slow one down by, say, shooting him in the stomach, is useless.
Limited Psychic Abilities- The Dark Judges have psychic abilities. They can tell when people are near (though not passively, they have to be looking.
Phasing- Though it's mostly Judge Death's shtick (as the others have their own abilities), each Judge can phase their hands through solid objects.
Enhanced Strength- Each Judge is at the very least strong enough to lift and throw men several times their size.
Immortality- The Dark Judges cannot die of natural causes. They don't require sustenance, and have been seen surviving months at a time without air, light, etc.
Dimension Globes- Handheld dimension hopping devices which allow the holder to move into alternate universe. The Dark Judges 'acquired' them from friendly extradimensional visitors.

Judge Darkness.  Judge Darkness is a being made nearly of darkness, being able to manipulate the shadows and change them into deadly weapons.

Weaknesses:
He is sensitive to light, and can be stopped temporarily with it.