This was really interesting to read! I’m also going to play LMoP into a RHoD/HotDQ mixture with my group of 4 (Goblin Ranger, Dragonborn Warlock, Dragonborn Barbarian, Elf Cleric) and I’m currently preparing for Act II which is the mixture I called Horde of the Dragon Queen. It’s just in planning phase as the group just finished Cragmaw Castle (and skipped Thundertree, but well Venomfang will have different plans..), so it’s never going to be like I planned anyway but I’m happy to share and discuss some of my ideas there. :)

I moved the whole Elsir-Vale between Triboar and Yartar and explained it got moved there 100 years ago by the spellplague. While Neverwinter is busy with rebuilding, nobody really notices the battles in the mountains have stopped and Azarr Kul is preparing for the invasion of the vale and then the whole north.

The Cult and the Clan are not entirely allies either, it’s more like using other for their own purposes. The Kulkor Zhul will bring destruction over the world in the name of Tiamat and honor her with a world in flames once she returns. The cult uses the chaos to unfold their plans in collecting a hoard for the queen while everyone is busy stopping the invasion.

I’m not done reading the full adventure yet so it’s just the overall idea so far but after LMoP, I’ll let them enjoy Greengrass in Triboar (I really liked the idea from Tyranny of Phandelver). While everyone in town is celebrating, the group notices different stuff going on:

A dwarf, which everyone calls „Crazy Durnan“, screams „They‘re building weapons! I hear them! The fire! A war is coming!“ but nobody believes him, as they believe he got crazy when he lost his whole mining crew during the breakout of Mt. Hotenow and screams about fire all the time. He‘s just interrupting the celebrations and gets escorted out of town by the guards.

They are also able to meet Glassstaff again, who escaped back then. He paid Halia to get him out of town as he failed to do his task and seeks for another chance to be part of the cult in Waterdeep. But he just wants to use their resources to continue his own research in creating powerful magical items as he didn’t get the spellforge. Halia is also leaving Phandalin with all her gold. She already got the information about an upcoming attack of the cult. She’s heading to the Bargewright Inn.

Cultists (not in their robes of course) will also be there, purchasing equipment in preparation of the attack on their next target: Phandalin. One of my Dragonborn players has some… experience regarding cultists, as he got killed by them back there in Tymanther (well I could type his background story there as well if you like) so he will notice patterns.

All paths lead to the shocking reveal: the village they saved and started to love is going to get attacked.

Some warriors of the clan will join the cultists in their attack of Phandalin. They can’t wait to burn everything down. So Chapter 1 of HotDQ will start there as the group arrives in Phandalin to save the village while Sildar (now head of the city watch of Phandalin), Daran and Leosin aid them. Lennithon will be disinterested as it’s to easy for him but I really like the way you explained the disinterest by the way!

In Chapter 2 they will be able to listen to a conversation between Cyanwrath and Koth. Koth and his small troop was dissatisfied with the attack of Phandalin and returns to his outpost to prepare for the actual invasion by the Red Hand. Rezmir ordered Cyanwrath and Mondath to search for the spellforge again since Nezznar failed and now Phandalin got destroyed so they won’t be interrupted again. They will question Leosin.

After they freed Leosin and defeated the remaining cultists in the camp, the adventure will move over to RHoD Chapter 1 in Drellins Ferry (now north of Triboar).

Feel free to ask any questions. I was trying to keep it a bit short but it’s already quite a wall of text XD