Shadewither Key
This palm-sized talisman hangs on a string of braided bark fibers. It resembles a leaf from some unknown tree similar to oak, carved from jade and then dipped halfway into black ink that looks wet despite feeling completely dry. The gate key was originally created to open the aiudara known as the Seventh Arch. In recent years, corrupting magic has given it additional, stranger powers.
When you wear and invest the Shadewither Key , shadows gather around you. You gain a +1 item bonus to Stealth checks.
Activate ◆◆ Interact
Activate—Umbral Double ◆ (concentrate, manipulate)
Effect You touch the Shadewither Key and command the shadows it casts around you to peel away. The shadows form an umbral double that resembles you in every way except for its fiery red eyes and the expression of wicked delight on its face. The double occupies the same space as you and attempts to intercept any attacks aimed at you. A creature must succeed at a DC 11 flat when targeting you with an attack, spell, or other effect; on a failure, they hit the shadowy double instead of you. The effect lasts for 1 minute or until the double is hit, whichever comes first. Once the double is hit, it's destroyed. As long as the double exists, you don't gain the Shadewither Key's item bonus to Stealth checks.
Traits
Items with this trait are artifacts. These magic items can't be crafted by normal means, and they can't be damaged by normal means. Artifacts are always rare or unique.
An item with this trait is cursed to cause trouble for its owner. A curse isn't detected when the item is identified, though a critical success reveals both the presence and exact nature of the curse. Cursed items can't be discarded once they've been triggered or invested the first time. The item can be removed only if the curse is removed.
Effects and magic items with this trait involve false sensory stimuli.
A character can invest only 10 magical items that have the invested trait. None of the magical effects of the item apply if the character hasn't invested it, nor can it be activated, though the character still gains any normal benefits from wearing the physical item (like a hat keeping rain off their head).
This magic comes from the primal tradition, connecting to the natural world and instinct. Anything with this trait is magical. A creature with this trait is primarily constituted of or has a strong connection to primal magic.
This magic involves shadows or the energy of the Netherworld.