Thundertree is an abandoned village a day’s travel from Neverwinter. The eruption of Mount Hotenow, which caused quite a catastrophe for Neverwinter half a century ago, destroyed the village of Thundertree. Erdan, the druid of the group who is prone to visions and nightmares, dreamed that the eruption of Hotenow was caused by a group of chanting fire cultists, but probably didn’t go as planned, as the cultists were killed in the event. What remained in Thundertree was mostly abandoned houses, with a population of ash zombies and twig blights. The group had gone to Thundertree to meet the druid Reidoth, who was supposed to know the location of Cragmaw Castle. Their “pet goblin” Droop also claimed to be able to find the way from Thundertree to Cragmaw Castle. They met Reidoth, who was able to provide a safe haven in the village, as well as the directions needed.
After clearing out most of the village from monsters, the group came across another group which likewise was engaged in fighting twig blights. That group was wearing blue armor and white robes, beset with feathers. They explained that they were from a club of aerial enthusiasts, and were in Thundertree to try to tame a griffon nesting here, or get eggs from his nest to raise as aerial mounts. The heroes agreed to accompany them to the griffon’s lair in the highest tower of Thundertree. But once there the air cultists tried to becalm the griffon by offering the adventurers up as sacrifice, so the group ended up killing both the cultists and the griffon. They were able to make the link between a symbol the cultists carried and the same symbol they had seen on a letter to Glasstaff in Phandalin.
On the way to Cragmaw Castle the group tried to question Droop for information about the castle. That was somewhat complicated by the fact that Droop could only count to 3, and used “3” as an answer to any question about numbers in which the answer exceeded 2. Not trusting the goblin’s offer to negotiate safe entry into the castle, they knocked him out and attached him to a tree, guarded by the paladin (the player was absent that session). Instead they built a camouflage out of branches and approached the less guarded south side of the castle at night. From there they could see into the banquet hall, but the goblins there didn’t look out the arrow slits. So they managed after a few attempts to unlock the side door. But they didn’t like the idea of advancing with the goblins in the hall behind them, so they decided to attack there.
From there they moved clockwise room by room. That enabled them to eliminate most guards in small groups. However it did move them more towards the entrance of the castle, instead towards the throne room. The toughest fight was against a group of hobgoblins. Popée the sorceress used a web spell on them, but between succeeded saving throws initially and later the web wasn’t all that effective. Then they tried to burn the web, but in 5E that deals only 2d4 damage, and the player rolled double 1s, so the spell wasn’t really a big success. The hobgoblins however had an ability with which they dealt an extra 2d6 damage if next to an ally. And two of them rolled critical hits, which doubles the number of dice on all damage, knocking the druid out of his bear form. After another fight in the central chapel of the castle the group had enough and decided to go back into the woods to take a long rest.
Returning to the castle they found that the bugbear King Grol had obviously noticed that the group had raided his castle and killed most of the goblinoids in there. So King Grol has gathered all the remaining defenders in the chapel, including a priest from the air cult. That ended up being a tough fight, with Theren being knocked down to zero health, but then rescued. The air cultist priest was a real menace, with a dust devil spell that prevented the archers and casters from sniping from the back. But Popée used a scroll of lightning bolt on King Grol and his pet wolf, killing the wolf and seriously damaging the bugbear. Soon after all the bugbears were dead. The priest tried to transform into gaseous form and flee, but didn’t make it out of the arrow slit in one round and concentrated fire killed him before his next round. At this point it had gotten rather late, and we ended the session.