A disenchanter is an annoying monster found in the deeper levels of the dungeons and in Gehennom. The random R at the Castle may be a disenchanter, but they are otherwise only randomly generated in Gehennom. Its attack can decrease the enchantment of weapons and armor (as well as doing an unthreatening amount of damage), and reduce charges on items you hit it with.
Hitting a disenchanter with a weapon will decrease the enchantment of the weapon, unless it is an artifact, in which case it has a 90% chance of resisting. Hitting a disenchanter with any chargeable object will decrease its charges - the game treats charges and enchantment the same. Wands are therefore not a good alternate weapon to use to avoid disenchanting your main one.
Disenchanters are the deeper-level equivalent of rust monsters. Disenchanters remove only positive enchantment or charges; a disenchanter will not remove negative enchantment or cause an unenchanted item to gain negative enchantment.
- The disenchanting claw attack is subject to magic cancellation, so make sure your armor grants magic cancellation of 3. This does not prevent the passive disenchanting attack.
- Engrave Elbereth. Your weapon may still be disenchanted if you attack and hit.
- Cancel the disenchanter via a wand of cancellation, the spell, or by hitting with Magicbane. Canceled disenchanters can not disenchant, even through their passive attack.
- Use ranged attacks. Be aware that your projectiles will be disenchanted; prefer spells or wands or use a sling, as rocks are plentiful and can't be enchanted anyway. In a game where you had many scrolls of enchant weapon, you might choose to throw from your pile of +7 daggers; for though the resulting +6 daggers will not stack, they are much preferable to disenchanting your artifacts or armor.
- Unwield your weapon and punch the monster to death, or use an unenchanted weapon. Bear in mind that any gloves will be disenchanted if you hit with gloved hands.
- Wield a junk weapon and hack the monster to death; pick-axes work well for this, as do some class' starting secondary weapons. Avoid using a Unicorn horn - it is two-handed, and if it get cursed, you lose the use of your hands. By the time you meet disenchanters, curse inventory spells are also a concern and you probably can't pray for help. Getting stuck with a cursed unicorn horn in Moloch's Sanctum can be lethal(it really happened).
- Let your pet do the killing if it's strong enough and does not wield weapons.
- Genocide. Because rust monsters are not much of a threat once the player reaches Gehennom, and blessed scrolls of genocide are best reserved for monsters whose entire class is difficult (liches, for example), disenchanters can be a good target for a single species (uncursed, if from a scroll) genocide.
- Don't try to kick them to death. This will disenchant your boots.
Disenchanters can be useful to classes who cannot reliably cast drain life, as they can be used to selectively reduce the enchantment on a weapon or a piece of armor so it can be re-enchanted to a higher level. To reduce the enchantment on a piece of armor, wield it and strike the disenchanter with it once. Just be careful, if you try this with your cloak, you should wear a substitute for MC3, in order to nullify it's draining active attack.
In UnNetHack eating a disenchanter corpse has a 50% chance of removing a random intrinsic, in a way similar to being hit by a gremlin at night. While potentially dangerous, this could also potentially be used to get rid of harmful intrinsics gained accidentally.
Ask not, what your magic can do to it. Ask what it can do to your magic.