In GruntHack, DynaHack and FIQhack, an object property is a magical attribute associated with a non-artifact item which does not normally have that property; for example, a leather cloak of fire resistance would have the "fire resistance" property. Only weapons (including weapon tools), armor, rings, and amulets can have object properties.
Randomly generated objects have a 1 in 100 (GruntHack) chance of being generated with at least one property.
A wish can apply a single non-detrimental property to the object wished for. Of those objects, each has a recursive 1 in 250 chance of having an additional property applied to it. In DynaHack, only magical wishes can apply an object property and even then they can only be applied on non-magical base item.
Wizards can sense object properties before they are identified, and see a "magical" prefix before the relevant properties are known. In DynaHack all players can sense object properties regardless of role.
Properties applicable to most or all items
- Reflection: Grants reflection. Not applicable to projectile weapons, boots, gloves, or helmets.
- Searching: Grants automatic searching. Not applicable to projectile weapons.
- Warning: Grants warning. Not applicable to projectile weapons.
- Stealth: Grants stealth.
- Telepathy: Grants extrinsic telepathy, as the helm of telepathy or amulet of ESP. Not applicable to projectile weapons.
- Fumbling: Grants fumbling.
- Hunger: Grants hunger.
- Aggravation: Grants aggravate monster.
Properties applicable to weapons
- Fire: Deals double damage to non-fire-resistant targets; has a chance of destroying potions, scrolls, and spellbooks.
- Frost: Deals double damage to non-cold-resistant targets; has a chance of destroying potions.
- Vorpal: Single-handed weapons behead non-headless targets on a 1-in-20 chance (and jabberwocks 100% of the time), as with Vorpal Blade; double-handed weapons bisect small creatures and cut deeply into large creatures on a 1-in-20 chance, as The Tsurugi of Muramasa. Only applicable to bladed weapons.
- Thirsty: Drains life of non-drain-resistant targets, as Stormbringer and The Staff of Aesculapius.
- Detonation: Explodes upon hitting something after being fired or thrown. Only applicable to projectiles and launchers.
Note, that in very last development version of GruntHack the extra fire and frost damage was changed from 2x to d6. This is the version of object properties that was incorporated in DynaHack. The version of GruntHack that can be played on grunthack.org does not have these changes.
Properties applicable to armor
- Fire resistance: Grants fire resistance.
- Cold resistance: Grants cold resistance.
- Drain resistance: Grants drain resistance.
- Speed: Grants extrinsic speed, as boots of speed.
- Oilskin: Permanently greased, as the oilskin cloak. Note: for wishing purposes in Grunthack, the base material must be cloth to get oilskin.
- Power: Sets strength to 25, as gauntlets of power.
- Dexterity: Grants a +(enchantment) bonus to dexterity, as gauntlets of dexterity.
- Brilliance: Grants a +(enchantment) bonus to intelligence and wisdom, as a helm of brilliance.
- Displacement: Grants displacement, as the cloak of displacement.
- Clairvoyance: Grants clairvoyance, as though wearing a cornuthaum as a wizard.
DynaHack works mostly similar to GruntHack with some caveats
- Property generation is different
- Vorpal no longer randomly generates
- Weapons and weapon-tools get properties (level difficulty)/100 of the time
- Armor get properties 1/100 of the time (similar to GruntHack)
- Jewelry gets properties 1/250 of the time (except for the Amulet of Yendor)
- You can no longer wish for properties on items with innate powers (Oilskin doesn't count as an innate power, things that change attributes do). Note that "oilskin cloak of displacement" is parsed as a cloak of displacement with the oilskin property, meaning it wont get through. Use "slippery cloak of displacement" instead.
FIQhack has the following caveats compared to Grunt/Dyna
- Property generation is different
- Vorpal doesn't generate
- Weapons and weapon-tools get properties (level difficulty)/100 of the time (similar to DynaHack)
- Magical armor get properties half as often
- Jewelry get properties 1/4 as often as weapons
- Bags can generate with the oilskin property (which functions), with equal probability as weapons getting properties
- The following properties generate 10% as often: reflection, telepathy, speed, power, dexterity, brilliance, displacement
- Added properties
- You cannot wish for properties at all.
- Weapons can no longer generate with fumbling (but armor still can).
- "Properties applicable to most or all items" no longer includes projectile weapons, which only can have fire, cold, shock, thirsty or detonation.
- Weapons can't have both the fire and cold property.
- Detonations, rather than always being fire based, is cold based with weapons of frost, lightning based with weapons of shock, otherwise fire based (A weapon of frost and shock will have cold explosions, a weapon of shock and fire will have lightning explosions, a weapon lacking all 3 will have fire explosions).
- Price-wise, if an object has any property, its base price is increased by 50. In addition to this, each property double the overall price -- so if something's base price is 5, one property would have it at 110 ((50+5) * 2), 220 ((50+5) * 2 * 2), etc.