I accidentally swapped the covetous monsters teleport to stairs to heal
but instead of changing it back like it was, now make those monsters
teleport to either upstairs or downstairs - some of them will go up,
others go down.
... you will also get a message when a seen stinking cloud
or the one surrounding the hero dissipates.
Original feature comes from Fourk, but this version (with some
minor changes) comes from xnethack by copperwater <aosdict@gmail.com>