Instadeath

An instadeath, short for instant death, is a mechanism which, when applied, guarantees that you die immediately, even if you had hundreds of HP. If you have a wand of death or finger of death, then you can instadeath some monsters.

Causes of instadeaths are:
 * Be hit by a wand of death.
 * Zap yourself with a wand of death, especially a cursed one. ("You irradiate yourself with pure energy!")
 * Zap a wand of death at a monster, and let the ray bounce off a wall and hit you.
 * Let the Gnome With The Wand Of Death (GWTWOD) attack you.
 * Be hit by a magic spell, the finger of death. The Wizard of Yendor and possibly some other monsters know this spell.
 * Occasionally, poison causes an instadeath, unless you have poison resistance.
 * Do something with a drawbridge.
 * Drown.
 * Intentionally level teleport yourself to certain levels.