So. There I was, in a labyrinth, with a deck of cards sitting there.
I said "Hmm, let me exhaust this deck of cards, maybe I will get a shuffle
or something" and drew. I got warpwright... which put a teleportation trap
between me and the stairwell, like so:

 ######
 +@^.<#
 ######

I was an Okawarite, and had no means of crossing the boundary. Had I been
able to blink, I would have been guaranteed success with the door closed;
unfortunately, I used my only blink scroll with the door open, and my
blink was made uncontrolled. [1] So I was left with three ways to get out
of the labyrinth:

 * Blink from the safe square.
 * Get banished.
 * Get a teleport into that area (1/1800 chance, according to ##crawl)

Okawaru penance only sends you random monsters; I abandoned him anyway
in the hope that a monster would have a distortion weapon and so that
I would have some food source. I had a book of War Chants on me, though no
spells memorized [2], so I memorized Berzerker Rage, put on plate mail,
and proceeded to Glow myself into oblivion in the hope of picking up a
blink mutation. I did not.

Okawaru only sent enemies once, and I killed them without getting a weapon
of distortion. I starved to death. This leaves me with two questions:

 1. How can I avoid this ever happening to me again?

The answers, to me, are either "don't draw from decks ever again"
(it could also, apparently, have been tomb and put a wall in place
or something) or "get spoiled on decks," which I had avoided doing.
I'll probably do both.

 2. Is this something that should be avoidable or escapable if
    someone else does it?

This is a tricky question. On the one hand, this is a really awful way
to die, and I think most people would have been way more upset than I
am, which is certainly not "totally chill." [3] On the other hand, what
could be made different? The teleportation trap is fine, the card is (I
think) fine, and the labyrinth is fine. The only suggestion I can come
up with that I don't discard as intolerable is putting an Abyss portal
in every Labyrinth (or, if you want to be really harsh, and Abyss or a
Pan portal...). But I don't really like that either.

I'm curious if anyone has any answers to either of those two questions;
as far as whether it's YASD or YAAD it's probably both, since playing
with the deck was stupid but being left in an untenable position by it
was annoying.

Also, it is drinking time now.

-r.

[1] I remember using controlled blink to cross lava in a labyrinth before,
so I just assumed it would be fine.  Was this in a dream? In 0.2?

[2] Yes, it was a CeEE with no spells memorized. I was playing it because
it was the second-lowest-scoring combo on CAO, not because I wanted to
play an earth elementalist. I totally have the high score for it now! :)

Due to Warpwright and its relatives, I consider drawing from an
unloaded deck next to a graph-theoretic cutpoint "asking the RNG to
flatten you".  YASD if unanticipated, YAAD if anticipated.

As a matter of appropriate background knowledge, I do not think
detailed documentation is in-theme for non-Nemelexites; thus, it
doesn't belong in the manual. Even in-game, any detailed documentation
should be keyed to religious history.  (Say, maximum ever Nemelex
piety.  Current Nemelex piety is also defensible, and doesn't require
any new data structures.  Or maybe time spent as a Nemelexite.)