Ruins of Adventure
Crossbow bolts with red metal shafts and red and yellow fletching.
Anyone struck by one of these crossbow bolts must save vs, death magic or become instantly ill, suffering a loss of 1d10 poison damage. Each round thereafter, the target must make another save or suffer another 1d10 poison damage. The effect continues until the target succeeds on a save or a cure disease (or equivalent) spell is cast upon the victim.