IndexError

Level 1 of the Dungeon
(0, 0, D:1)
  a +0 short sword
(4, -9, D:1)
  a +0 rapier
(4, 8, D:1)
  a +0 leather armour
(5, -12, D:1)
  a +0 short sword
  a kobold skeleton
(6, -24, D:1)
  a +0 falchion
(10, -1, D:1)
  a +0 kite shield
(11, -23, D:1)
  a rat skeleton
(12, -27, D:1)
  3 stones
(12, -21, D:1)
  a +0 club
  a +0 short sword of speed
  a kobold skeleton
(17, 10, D:1)
  a +0 rapier
  a goblin corpse (skeletalised by now)
(25, -24, D:1)
  a bat skeleton
(30, -28, D:1)
  a hobgoblin skeleton
(30, -3, D:1)
  a +0 club
  a goblin skeleton
(32, 6, D:1)
  a +0 dagger
  4 stones
  a rat skeleton
(38, -10, D:1)
  a +0 ring mail
(41, 3, D:1)
  a +0 spear
  a gnoll skeleton
(45, -17, D:1)
  a +0 spear
(48, -19, D:1)
  a frilled lizard skeleton
(52, -8, D:1)
  a +0 rapier
(56, -2, D:1)
  4 poisoned darts

Level 2 of the Dungeon
(0, 0, D:2)
  a +0 buckler
(1, 28, D:2)
  a +0 ring mail
(2, 20, D:2)
  8 stones
(18, 10, D:2)
  a serpent talisman
(22, 8, D:2)
  a bat skeleton
(24, 31, D:2)
  a quokka corpse (skeletalised by now)
(27, 10, D:2)
  2 stones
(28, 34, D:2)
  a +0 kite shield
(29, 32, D:2)
  a +0 hand axe
(30, 18, D:2)
  a ball python skeleton
(33, 18, D:2)
  a hobgoblin skeleton
(36, 4, D:2)
  a +0 dagger
(38, 28, D:2)
  a +0 falchion
  a goblin skeleton

Level 3 of the Dungeon
(0, 0, D:3)
  a +0 whip
(10, 3, D:3)
  a hobgoblin skeleton
(11, 6, D:3)
  a +0 robe
  a +0 dagger
(12, 1, D:3)
  a +0 short sword
(16, 0, D:3)
  an iguana corpse (skeletalised by now)
(22, 26, D:3)
  a flux talisman
(25, -7, D:3)
  a +0 ring mail
(26, 21, D:3)
  a +0 trident
(27, 27, D:3)
  a scroll of silence
(29, 2, D:3)
  6 poisoned darts
(29, 18, D:3)
  a hobgoblin corpse
(30, -2, D:3)
  a rat corpse (skeletalised by now)
(30, 35, D:3)
  a +0 dagger
  2 datura-tipped darts
(31, 24, D:3)
  a +0 hand axe
(36, 29, D:3)
  a +0 whip
  a +0 leather armour
(36, 30, D:3)
  a +0 hand axe
(36, 31, D:3)
  a hobgoblin corpse
(42, 21, D:3)
  a +0 dagger