Mister Sandman (Fallout 4)

Mister Sandman is a perk

Effects
Increased damage from silenced weapons.

With this perk, the player character has the option to silently kill any sleeping Human or ghoul. Mister Sandman is performed in sneak mode, with a "Sandman Kill" option appearing to the right of the regular "pickpocket" one. When used, a short murder animation follows, in which the player character slits the victim's throat, accompanied by a cartoony jingle. Unlike in Fallout 3 and Fallout: New Vegas, no XP is awarded for Mister Sandman kills.

Behind the scenes
The name of the perk is in reference to The Chordettes 1954 song "Mr. Sandman". While the perk has existed since Fallout 3, the song itself did not appear in any released game until Fallout 76.