By Kate Nepveu
Version 1.1; created April 16, 2001; last updated April 30, 2002 to clarify ways of engraving.
According to the Guidebook, in its discussion of the E)ngrave command,
"Engraving the word "Elbereth" will cause most monsters to not attack you hand-to-hand (but if you attack, you will rub it out); this is often useful to give yourself a breather. (This feature may be compiled out of the game, so your version might not have it.)"
(You can tell if Elbereth is complied into your version of the game with #version or Meta-v.)
Thus, Elbereth can help protect you from attack. It is also a popular way to protect stashes of equipment in the dungeon, even those in containers, since gelatinous cubes will eat any container except an ice box. Note that something (an item, you) must be on the space where Elbereth is engraved for monsters to stay off the space. Elbereth on an empty space has no effect. Also, the effect of Elbereth is case-insensitive, but you exercise wisdom if you engrave it thus: "Elbereth". (You can also bury Elbereth in the middle of some other letters and it still works: "fooElberethfoo".)
An identical effect can be obtained by dropping a scroll of scare monster. In 3.4.0, you will be told that "<affected monster> turns to flee!" when you drop the scroll or finish engraving Elbereth. (However, scrolls of scare monster are a poor choice to protect your stash, since they disintegrate once picked up enough.)
[Elbereth comes from J.R.R. Tolkien's writings set in Middle-Earth, particularly The Lord of the Rings and The Silmarillion; it was the Elves' name for a goddess they particularly revered. A song in her praise proves to have bad effects on Sauron's minions in The Lord of the Rings. See also "Elbereth" under the specify command, "/".]
It's easier to say what doesn't respect Elbereth. The following will attack you anyway:
Note that although K (Keystone Kops, Kop Sergeants, etc.) are considered human for purposes of cannibalism and sacrifice, they do respect Elbereth.
In addition, peaceful monsters will not respect Elbereth. Obviously, they won't attack you, but they will walk over the space—not picking anything up, but possibly eroding the Elbereth protecting your stash. (Protecting that space from peaceful monsters is left as an exercise for the reader.) How do you tell if a monster is peaceful? Use the "/" command to identify the monster (and you'll see, for instance: "o an orc (peaceful hill orc)").
Well, first, it's best to engrave when you've got all your wits and senses about you. That is, you have the following chances of messing up each letter if you are: blind (1/9), confused (1/12), stunned (1/4), or hallucinating (1/1). So don't count on engraving Elbereth correctly if you're impaired.
You can, of course, engrave in a number of different ways. The relevant qualities are summed up below, and then each method is detailed.
The importance of duration should be obvious. Speed is important because while you are engraving, anything can and will attack you: you don't get Elbereth's protection until you're finished engraving. What's more, the attack won't interrupt your engraving—once you start engraving, you can't protect yourself until you are done. For this reason, if you are under attack, you should only engrave by a fast method. In addition, if you are under attack and want to add an Elbereth to a square that already has one, only add one; if you add more than one, you can be attacked before you finish; think of it as obscuring the monsters' view for too long.
Thus, if you need to write Elbereth with just one +0 non-athame, first engrave "Elb" and then add "ereth" to the engraving. Odd, but true, because of how engraving is treated: engrave 1-3 letters and lose one enchantment from a weapon; 4-5, lose 2; and 6-7, lose 3. A -3 weapon is too dull to engrave with. (Of course, you could also use two +0 weapons, or one weapon at +1 or greater, if practical.)
You can also scrawl on the floor in blood, if you write with your fingers while polymorphed into any V or & (same chance of screwing up letters as if writing in the dust), or scribble on the floor with a magic marker. The first is unlikely to come up all that often, and the second is unwise because usually you have much better uses for magic marker charges. However, they're there if you need them.
Thanks to all of rec.games.roguelike.nethack, and in particular to Zack Weinberg, Shaman, Ross Presser, Robert R. Schneck, Keiran, Topi Linkala, Esque, and Dylan O'Donnell.
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