Dark rangers are elven rangers with a different focus. The dark ranger is a cunning hero, adept at manipulating opponents. Forcibly raised from the dead, the former rangers of Quel'Thalas enjoy nothing more than sowing dissension and hatred within the enemy ranks. Dark Ranger Lyana leads the attack against the Derelict Strand near Vengeance Landing.
To achieve this look I used these items.
An alternative hood with red eyes - Malefic Mask of the Shadows from Gruul.