Orc-arrows

It was common among the Orcs to use poisoned weapons of all kinds, and that applied in particular to the black-feathered arrows that they favoured. The custom of poisoning arrows among the Orcs apparently dated back at least as far as the First Age. We have several accounts of Men being slain by Orc-arrows from those times, including Hador's son Gundor, as well as the outlaws Orleg and Andróg (though only in Andróg's case is poison specifically mentioned).

Rather more important to history was the fate of Isildur at the beginning of the Third Age. Escaping the Disaster of the Gladden Fields he fled across Anduin and, though he was wearing the One Ring and therefore invisible, Orcs were able to hit him with their poisoned arrows. Thus the Ring was lost in the river, setting in motion the events that would lead to the War of the Ring three millennia in the future.

The use of poisoned arrows by the Orcs was countered by their mortal enemies the Drúedain, who created even more virulent poisons to attack the Orcs in turn. The tradition among these people was that their poisons should only be used against the Orcs, but folklore among Men remembered only their use of poisons, and the Men of Rohan feared their poisonous darts.