IndexError

Level 1 of the Dungeon
(0, 0, D:1)
  a +6 ring of dexterity
(3, -5, D:1)
  a rat skeleton
(5, 0, D:1)
  a +0 mace
(9, 29, D:1)
  a +0 leather armour
(21, 21, D:1)
  a +0 club
  a goblin skeleton
(25, 20, D:1)
  a rat skeleton
(25, 21, D:1)
  a +0 dagger
  a goblin skeleton
(29, 9, D:1)
  a +0 sling
(33, 7, D:1)
  a frilled lizard skeleton
(33, 8, D:1)
  a frilled lizard skeleton
(37, 0, D:1)
  a scarab talisman
(40, -1, D:1)
  a +0 short sword
(44, -7, D:1)
  a +0 hand axe
(44, 0, D:1)
  a hobgoblin skeleton
(46, 0, D:1)
  a hobgoblin skeleton

Level 2 of the Dungeon
(0, 0, D:2)
  a +0 club
  a +0 sling
  a goblin corpse (skeletalised by now)
(2, -40, D:2)
  a +0 club
  a goblin skeleton
(3, -46, D:2)
  a +0 dagger
  a stone
(3, -41, D:2)
  a +0 dagger
(5, -34, D:2)
  a +0 club
(10, -38, D:2)
  a +0 sling
(11, -40, D:2)
  a +0 dagger
(13, -38, D:2)
  a +0 dagger
(18, -12, D:2)
  a +0 hammer
(36, -24, D:2)
  a +0 dagger
  a goblin corpse (skeletalised by now)
(40, -45, D:2)
  a rat skeleton

Level 3 of the Dungeon
(0, 3, D:3)
  a river rat corpse (skeletalised by now)
(34, 2, D:3)
  a hobgoblin corpse (skeletalised by now)

a sewer
(0, 0, Sewer)
  a +0 club
  3 stones
  a kobold corpse
(3, -1, Sewer)
  a +0 short sword
  3 stones
  a kobold corpse
(8, -1, Sewer)
  a ball python corpse
(12, 6, Sewer)
  a rat corpse
(19, 0, Sewer)
  a rat corpse
(20, 3, Sewer)
  a rat corpse
(20, 4, Sewer)
  a rat corpse
(21, 2, Sewer)
  an adder corpse
(21, 3, Sewer)
  a rat corpse
(21, 5, Sewer)
  a rat corpse
(22, -2, Sewer)
  a rat corpse
(23, -2, Sewer)
  a rat corpse
  a river rat corpse
(24, 5, Sewer)
  a rat corpse
(26, 5, Sewer)
  a rat corpse
(34, -2, Sewer)
  a rat corpse (skeletalised by now)
(40, 11, Sewer)
  a rat corpse
(46, -1, Sewer)
  a +0 whip
  2 stones
  a kobold corpse
(47, -1, Sewer)
  a +0 short sword
  4 poisoned darts
(49, 13, Sewer)
  a potion of haste
(49, 14, Sewer)
  a potion of mutation