Dagger of Whistleblowing (5e Equipment)
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Weapon (dagger), uncommon (requires attunement)
Whenever you make a Dexterity (Stealth) check while wielding this dagger, you are considered proficient in the Stealth skill and add double your proficiency bonus to the check, instead of your normal proficiency bonus.
Curse. This dagger is cursed, and attuning to it curses you until you are targeted by the remove curse spell or similar magic. As long as you are wielding this weapon or having it in your person, the weapon makes a sharp whistling noise that can be only heard by a creature within 10 feet of you that does not know your presence. A creature who hears the whistling noise automatically succeeds on the Intelligence (Investigation) or Wisdom (Perception) checks to notice you.