The Winter Druids' Legacy

From the introduction: The Winter Druids’ Legacy picks up where The Frozen Necromancer left off. After defeating or negotiating a deal with Ralekai Gravemore, the characters are approached by the ghost of Feriae the Wise, a druid of Minas Herion. She informs the characters of the Luna Valley’s history with Xancrown, a mighty plague demon locked away beneath the vale. A comet recently struck the valley and melted the Ice Tongue Glacier that covered the area.