The Nighthawks (also known as the Guild of Death) are a guild of assassins that operate in the world of Midkemia. They work in stealth and are recognizable by the golden chain necklace with a pennant of an ebony hawk which all members of the guild wear. Sometimes, they also don a black gambeson with a golden hawk emblazoned. Most Nighthawks are fanatics who would rather commit suicide than allow themselves to be captured, even possessing a hypnotic compulsion to "will" themselves to death.
Nighthawks were once employed by the Temple of Lims-Kragma. Their more fanatical practices, however, led to the assassin's guild being excommunicated. Regardless, a number of Nighthawks swear allegiance to dark powers. These assassins, upon death, would rise again as nearly unstoppable killing machines known as "Black Slayers". The Nighthawks, as an organization, was crippled when their hideout in Krondor was destroyed by Kingdom soldiers aided by Jimmy the Hand.
A number of Black Slayers were found to be employed by Murmandamus. They pursued Arutha and his party to Sarth, where they were repelled by the magic within the fortress' walls. Again, they hunted Arutha when the party was travelling from Moraelin, after successfully retrieving Silverthorn to cure Princess Anita. At the borders of Elvandar, however, the Black Slayers met their match in Tomas, a Dragon Lord incarnate.
With the organization in disarray, the surviving members fled to a hideout underneath Cavell Keep. When they caught a tresspasser in their lair, the man, Navon Du Sandau, convinced them of his magical abilities and eventually rose to become their leader. Once again employed by the moredhel, their exploits to come included poisoning a detachment of Kingdom soldiers in Romney and infiltrating Northwarden to prepare for the moredhel invasion. With the death of Navon, however, the organization faded into obscurity again, although, as Jimmy the Hand noted, they are harder to stomp out than cockroaches.