Sneaking into the Temple of Black Earth

(Scroll for tl:dr)
After pledging allegiance to the Lord’s Alliance, Arnogall, Aubrey, Balderpoor, Skonn and Sorin took off on their Hippogriffs and headed for a shrine called Gwaeron’s Slumber.  Sorin had wanted to go here as it was rumoured that his god, Gwaeron Windstrom was sometimes seen walking in the woods and would grant a boon to anyone who slept there.  They arrived at the edge of the woods where Sorin expected to find the area in a perpetual state of Autumn.  However the scene more closely resembled winter.  Sorin led them to the centre of the wood where he meditated and slept. When he woke Gwaeron approached and asked Sorin if he wished to receive a blessing.  Sorin agreed and knelt down before him.  Gwaeron raised his warhammer and struck Sorin’s head.  A fight ensued and “Gwaeron” revealed its true form and transformed into an evil giant known as an Oni.  It’s hammer caused a thunderclap that incapacitated the entire party and Sorin was knocked unconscious.  The Oni proved no match for The Adventurers™️ with Aubrey killing it with a powerful lightning bolt.  Now the Oni had been dealt with Sorin again slept in the clearing and this time received a vision suggesting he needed to defeat the three remaining elemental cults.

The party flew onwards to Red Larch finding it decimated with only a few buildings in tact.  They learnt that agents of Black Earth had detonated a devastation orb in the centre of the town.  They rested at the Swinging Sword and in the morning agreed a plan to infiltrate the Sacred Stone Monastery, a front for the Black Earth cult.  Based on the intelligence they had received from the Lord’s Alliance they decided their goal was to find the cult leader Marlos Urnrayle and take his weapon, the warpick Ironfang.  They would then be able to use Ironfang to close a portal to the the Plain of Earth, assuming there was one. Their plan was to find the location of an exit tunnel from the mines under the Monastery and then go straight to the Temple of Black Earth, bypassing the Monastery and most of the mines.  Their map showed where this tunnel was in the mines but they didn’t know where in the surrounding hills it came out.  Balderpoor was to shapeshift into a mouse and sneak through the Monastery, out through the tunnel and then signal the rest of the party.  They set off at night and during the day Arnogall corrected some bad grammar at the blacksmith’s, Aubrey and Skonn went out on the lash and Sorin and Balderpoor helped the townsfolk rebuild the town.

The plan worked well and Balderpoor was only spotted once but ignored because he was just a mouse.  He took the shortest route through the complex, ignoring any rooms he didn’t need to go through and came out of the tunnel into the surrounding countryside.  The rest of the party found him and they all went through the tunnel into the mines.  They carried a torch to light the way and this alerted a patrol of wandering Duergar who hid and surprised the party.  They were easily dealt with and the group continued to the stairs down to the temple.  The room next to the stairs was not identified on their map. Skonn’s curiosity got the better of him and he turned to find out what was in the room.  The iron door was locked so Skonn kicked it but it didn’t budge.  There was a roar from the other side and something bashed the door.  Skonn kicked again and the same thing happened.  On this third attempt the door fell inwards and he found himself face to face with an enormous Umber Hulk.  The hulk and Skonn roared as they charged each other.

(tl:dr The party searched for Sorin’s god who turned out to be an Oni in disguise; the infiltrated a monastery and Skonn found himself face to face with an Umber Hulk.)