Longsword of Warning

As long as this weapon is within your reach and you are attuned to it, you and allies within 30 feet of you gain the following benefits.

Alarm: The weapon magically awakens each subject who is sleeping naturally when combat begins. This benefit doesn't wake a subject from magically induced sleep.

Supernatural Readiness: Each subject has Advantage on its Initiative rolls.

Sap (Mastery): If you hit a creature with this weapon, that creature has Disadvantage on its next attack roll before the start of your next turn.

Versatile: A Versatile weapon can be used with one or two hands. A damage value in parentheses appears with the property. The weapon deals that damage when used with two hands to make a melee attack.

Proficiency: martial, longsword Source: Dungeon Master's Guide (2024) p. 324