In
NetHack, if you
offer many
sacrifices to your
god, never straying from the
True Path and
praying often (and you are at least level 3), your
deity may "crown" you the
Hand of Elbereth (
lawful), the
Envoy of Balance (
neutral), or the
Glory of Arioch (
chaotic). We all know what
Elbereth and
Balance are, but I cannot find a description of
Arioch. Oh well.
What actually happens is the following. You will gain several intrinsic resistances, provided you do not possess them already, including fire, cold, and poison. You will also gain the intrinsic ability to see invisible.
Most importantly, you will probably be given a weapon. If you are chaotic, this means the mighty Stormbringer! If you are neutral, you will receive a Vorpal Blade (and it goes snicker-snack!). If you are lawful and you are wielding a broadsword, it becomes Excalibur. Whatever you get is rustproofed, blessed, and given +1 enchantment.
The only disadvantage to being crowned is that your prayer timeout (the time you must wait between successful prayers) is increased by some amount. This is not actually that big of a deal, as long as you have a good food supply and/or a ring of slow digestion. Your prayer timeout can be decreased by further sacrifice and some luckstones.