Lost Mine of Phandelver
Venomfang is a young green dragon who made a lair in an old tower in the ruins of Thundertree village, after killing the giant spiders infesting the tower.
A local druid, named Reidoth, had noted the coming of Venomfang and knew the dragon’s presence would interfere with his work clearing Thundertree of it undead infestation. Additionally, Venomfang’s arrival had garnered the attention of a group of dragon cultists, led by Favric, that hoped to woo the dragon to their cause.
Following the druid request of slaying or at least scare away the dragon, the party meet the draconic create in his tower. However after some intense negotiations the party accepted the dragon deal of eliminating the cultist and the druid in exchange of the buried treasures beneath the tower and the revelation of the location of Wave Echo Cave.