I am building a series of dungeon delves and for the most part players will have unfettered access to any magic item for their level. With this kind of freedom I am looking to introduce some treasure items they can only be found and used in the dungeon they are delving. The treasure items I am thinking of will have less specific direct mechanical benefits (like you get +X to blah blah or you can use lah-di-dah Y times per day.)
The treasure items themselves can either be slotted items, wondrous items, or consumables. I am designing this as generic items though so instead of a "Greatsword" or "Longbow" or "Platemail" it will the most basic of slots like "Melee weapon," "Ranged Weapon," or "Armor." So any player who finds the specific treasure will be able to customize when they receive it to exactly something they can use under the category.
Here are a couple of my ideas so far for item properties in the style I am thinking. These may seem a little over powered compared to normal magic items, but they are meant to be. Many are supposed to have a good and bad side to the item.
Name: Warlord's Weapon
Description: This melee weapon while sheathed emits low growls, while drawn the weapon oozes with blood.
Property: When a character draws this weapon during an encounter all creatures including the wielder, flies into a bloodthirsty rage and will directly attack the nearest creature. Gain +2 to all attacks and defenses while in a rage. Save Ends.
Name: Construct Armor
Description: This armor looks like normal armor of its type except it has clockwork like gears embedded within especially in and around joints, once the armor is donned however the wearer finds it impossible to remove.
Property: This armor changes the wearer's creature type to construct, gaining all the benefits and penalties associated. While donned the wearer cannot heal hit points. Regardless if it is through magical means or naturally, and once the wearer reaches 0 hit points it dies. The armor fuses to the wearer and cannot be taken off once put on.
Name: Reflect Ring
Description: The Reflect Ring is a most powerful object against spellcasters. When a divine or arcane spell is cast against the wearer it glows light blue.
Property: When caster casts a spell that targets the wearer directly ("you" as a target in the description. Effect and area spells are not affected.) The wearer rolls on the table under the "spell turning" spell to determine what happens when that spell is cast. Note: if the result "both of you go through a rift into another plane." You are considered lost and thus dead for all game purposes.
These are just a few of the relic/artifact ideas I had. I would love some more ideas to throw into my campaign. Thanks and happy gaming.
Name: Rod of Portals
Description: The Rod of Portals is capable of breaking the bonds of reality, binding together two points through a magical rift.
Property: As a standard action, any character with a Rod of Portals can create two 5' portals. These portals must be cast on a mostly solid surface, such as earth or a wall, and have a range of Medium, using character level to determine the maximum range at which the portals may be created. Characters must be able to see the target location in order to create a portal.
Once the portals have been created, the areas they occupy are considered to be adjacent for all intents and purposes, including flanking, cover, and line of effect. Stepping or moving through a portal does not consume any additional movement.
If a portal is created in a space occupied by a creature, the creature must make a reflex save (DC 15+Character Level) or instantly pass through the portal, appearing in a square adjacent to the other portal. A successful reflex save allows the target to take a 5' step as a free action in any direction away from the portal. Unattended objects do not get a saving throw. In the event that unattended objects are used as weapons, make an attack roll against the target (10+Character Level). Use Environmental Damage or Weapon Damage to determine the effect on the target, whichever is higher.
*Edit: The Rod could also be replaced by a Ranged Weapon, in which case the effect's range would be determined by the range of the weapon.