The LEGO NEXO KNIGHTS Stone Monsters Accessory Set (853677) is a 23-piece LEGO set released in 2017 as part of the NEXO KNIGHTS theme. It includes accessories related to stone monsters and is designed for children aged 6 and up. The set features a LEGO character in the form of a monster and falls under the LEGO Subtheme of Accessory Sets, allowing children to enhance their NEXO KNIGHTS play experience with additional elements.