Halloween 2005 collectors

Description
During the Halloween 2005 update, Necrid Horsemen collectors appeared in four of the five main cities. Each was collecting a different collector item in preparation for the arrival of the Mad King, but all were offering the same spoils in return:
 * Absinthe
 * Ghost-in-the-Box
 * Squash Serum
 * Witch's Brew

Locations and Collecting

 * Ascalon City
 * Horseman Nurmangor collecting 3 Charr Carvings just south of the merchants.
 * Horseman Irimund collecting 2 Ornate Grawl Necklaces in the Crafters' Corner.
 * Lion's Arch
 * Horseman Vulgamor collecting 3 Decayed Orr Emblems in the square that housed the giant cauldron.
 * Horseman Malfein collecting 2 Glowing Hearts just to the north of Firstwatch Sergio.
 * Horseman Sorcein collecting 1 Feathered Caromi Scalp near Xunlai Agents.
 * Henge of Denravi
 * Horseman Darelum collecting 1 White Mantle Emblem near Magi Ket the Rare Scroll Trader.
 * Horseman Saralim collecting 2 Maguuma Manes near the henchmen and merchants.
 * Droknar's Forge
 * Horseman Calstein collecting 2 Stone Summit Badges near the giant skull.
 * Horseman Vilneous collecting 1 Feathered Avicara Scalp in Merchants' Row.