Efficiency

Level 1 of the Dungeon
(0, 0, D:1)
  a stone
(0, 1, D:1)
  a stone
(0, 2, D:1)
  2 stones
(1, 2, D:1)
  a +0 whip
  2 stones
  a bat corpse (skeletalised by now)
  a bat corpse (skeletalised by now)
(2, 2, D:1)
  a stone
(13, 9, D:1)
  a rat corpse (skeletalised by now)
(25, 16, D:1)
  20 stones

Level 2 of the Dungeon
(0, 0, D:2)
  16 gold pieces
(5, 5, D:2)
  a +0 hunting sling
(6, -5, D:2)
  a goblin corpse
(7, -19, D:2)
  25 stones
(12, -2, D:2)
  a +0 spear
(12, 0, D:2)
  a dart slug corpse
(15, 11, D:2)
  20 arrows
(16, 7, D:2)
  6 gold pieces
(17, -1, D:2)
  a +0 club

Level 3 of the Dungeon
(0, 0, D:3)
  2 stones
(0, 1, D:3)
  a stone

Level 4 of the Dungeon

Level 5 of the Dungeon
(0, 0, D:5)
  a scroll of identify
(9, 8, D:5)
  23 arrows