There are a lot of important factors to take into account when integrating a homebrewed item or monster into a campaign. One of the most essential is the monster's stat block. While the iconic Griffon of White Orchard could easily be represented in D&D using the standard griffon stats (an approach that also works for other monsters like the cockatrice, hellhound and wraith), intriguing monsters like the Drowner, Necrophage and Leshen will require more planning to adequately translate.
