By Kate Nepveu
Version 1.11; created May 10, 2001; last updated April 10, 2002 for 3.4.0.
A very scary demon prince (purple &), widely considered to be the most scary.
Ask the game (/), and it will tell you,
"Demogorgon, the prince of demons, wallows in filth and can spread a quickly fatal illness to his victims while rending them. He is a mighty spellcaster, and he can drain the life of mortals with a touch of his tail."
Let's count the reasons.
How bad are the sickness attacks? In 3.3.1, they were very bad: if Demogorgon got in one round, you didn't cure it, and then he got in another (two each round, for four total), you only had one more turn to live (technically, the end of the current turn, in which you might not have a chance to move, and then the next turn).
In 3.4.0, if the first disease attack is successful, then the second turns into a stun attack, which makes him slightly less scary.
Demogorgon, in vanilla NetHack, is neither randomly generated nor guaranteed: he has to be summoned. (He has his own lair in SLASH'EM.) There are, fortunately, limitations on who can summon him. (Warning: fractions ahead!)
Obviously, the longer you hang around any of these guys, the higher your chances of seeing Demogorgon.
Of the named demons, Orcus and Dispater (as well as Demogorgon itself) are spellcasters. In addition, the Wizard of Yendor (of course), master liches, arch-liches, titans, etc., are usually high enough experience level (monster level 16) to cast "summon nasties," but even golden naga or nalfeshnees could cast it (and have) if experienced enough.
Also, after you kill the Wizard of Yendor, sometimes he won't deign to reappear, but will just send some friends. This effect is treated the same way as the "summon nasties" spell, except that there will be no message in 3.4.0.
It won't matter if you can kill Demogorgon if you die of your illness anyway, so you must be fast enough to keep ahead of your illness. Preferably, this means being very fast: wear speed boots, quaff a potion of speed, or cast "haste self." Demogorgon's speed is roughly equivalent to "fast" (being zapped with a wand of speed monster); he gets five moves every four turns. What's more, he can cast "haste self," bringing him to five moves every three turns. You must also be unburdened, since being burdened slows you down. Drop those bags!
The only way to get sickness resistance as an intrinsic is to polymorph into a ghoul or any F. However, since this will give you terrible hit points and you can only wear limited (if any) armor, it's not a good idea. Sorry.
Guaranteed means of curing sickness:
So you can take care of your sickness; then what? Well, don't bother with polymorph, sleep, taming, or confusion: none of these will work, period, because he has an effective magic resistance of 100%. He's also immune to death rays.
If Demogorgon is right next to you and you need to buy yourself a moment--to heal up, put on that amulet of life saving, level-teleport/use the stairs to get the heck out of there, whatever--here are some options (if he's not right next to you, see "escape" below):
In terms of magic, Demogorgon will resist everything you throw at him. When an attack spell is resisted, it only does half damage; if you are casting the spell at a high enough level, though, it'll probably still be effective eventually. Note that magic missile and cone of cold are the only useful attack spells against Demogorgon. Try to bounce magic missiles if you can (off a wall, or off yourself if you have reflection) for multiple hits. If you are skilled or expert in attack spells, cone of cold is a particularly good idea: it does double damage against fire-resistant monsters, and thus will still do normal damage against Demogorgon when his resistance is factored in.
It is possible to simply beat Demogorgon to death, if you have enough means of curing sickness (or if he can't make you sick--see Elbereth, below)--people have done it with Magicbane, even. As with other demons, silver does extra damage against Demogorgon, making #twoweaponing with a silver saber (or silver dagger) a popular choice. Grayswandir, Frost Brand, and Demonbane are your best options among artifact weapons (note that Demogorgon is fire resistant); also consider Vorpal Blade for the possibility of an instant kill. The Tsurugi of Muramasa will not bisect Demogorgon; he's too large. Instead, on turns that you would have bisected a smaller monster, "You slice deeply into Demogorgon!", doubling your damage. See art2-341.html's table of damage, including average damage against major demons, for more information.
If you don't have faith in your ability to pound him to death, the most popular method of getting rid of Demogorgon is probably stoning:
If you really want to polymorph into something, consider using #monster as a black dragon to disintegrate Demogorgon. I think this would be pretty satisfying, too.
Other methods exploit Demogorgon's desire, like other monsters, to teleport onto the up stairs. If you can stand on the up stairs--by teleporting within the level, driving him upstairs to heal, or just being a step faster--he will have nowhere to teleport on that level, and thus will stay next to you. If you drive him to the next level up, you will of course have to go upstairs and then back down when he's next to you. There is a chance that you will not end up on the up stairs if this happens. Either try to lure him away and then beat him back to the stairs, or see the first suggestion:
Once you're on the up stairs with Elbereth inscribed, you can pound on Demogorgon freely while he can only cast spells at you from the next square. Note that this means he cannot make you sick!
Finally, if all else fails and you manage to get a step away from Demogorgon, escape! (See the start of this section for ways of getting a step away.) Once you're on a different level, you can prepare and then come back and face Demogorgon on your own terms. It is not advisable to leave him behind you.
If you can pick the place you confront Demogorgon, you might consider deliberately placing yourself near a hole, trapdoor, or level-teleport trap (if you don't have the Amulet or magic resistance), though beware that he might use the same means of escape to get away from you.
Much of the above can be combined to good effect. Probably the key thing is making enough time to take stock of your equipment and come up with a plan. The moral of the story: always have a means of engraving Elbereth and a means of curing sickness on hand.
J. Ali Harlow supplied the Monster
Eva R. Myers wrote a (nearly concurrent) SLASH'EM spoiler on Demogorgon that supplied paralysis and disintegration;
Jason Short, Dylan O'Donnell, James Killmond, Brave Ulysses, David Goldfarb, Pat Rankin, and Shaman all supplied valuable additions, corrections, and clarifications;
And of course, rec.games.roguelike.nethack supplied the inspiration, the nitpicking, and the feedback.
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