Efficiency

Level 5 of the Dungeon
(0, 0, D:5)
  8 gold pieces

Level 6 of the Dungeon
[Shop] Zuvyor's Gadget Shoppe
  (Shop contents are unknown)
(0, 0, D:6)
  14 stones
(3, 5, D:6)
  a +0 trident
(4, 8, D:6)
  9 gold pieces
(10, 7, D:6)
  12 gold pieces
(33, 10, D:6)
  a scroll of silence
(39, 6, D:6)
  14 gold pieces