A material for
nonmagical but still highly useful items in
Nethack. The oilskin
cloak, aka
slippery cloak, provides good magic cancellation and protects from the grab attacks of such monsters as
owlbears and
eels. The oilskin
sack protects all the objects contained within it from being damaged by the
elements: e.g., the sack can be safely
submerged without rusting
weapons or
armor in it, and fire traps will not burn
spellbooks or
scrolls, or boil
potions, contained in the sack. A common practice is to nest a
bag of holding inside an oilskin sack for increased
carrying capacity as well as waterproofing.