Actually quite good.
Having saved from the clutches of the Yuan-Ti a merchant's adopted daughter, a former soldier from one PC's army and a wild elf, the PCs stole back their horses which were in the village next to the Yuan-Ti compound and startey their journey back to Karaal, the city of sages, to get their payment for rescuing the merchant's daughter.
When they stopped for the night about midway, they were woke up by the sound of thunder. The wild elf and the PC rogue/ranger immediately saw the problem: the lighting lit the dry grass of the savannah on fire and the blaze was sweeping toward the PCs!
The PCs, saved one who dislike horses, ran toward their horses and galloped toward the nearest river. The fire was spreading unaturally fast. Two PCs fell from their horses while jumping from a small cliff. Three PCs were engulfed in the blaze, but managed to reach the safety of the river. In the flames, they saw snake-like figures.
At Karaal, one PC noticed a disturbing sight: the sage who had given him information had been hanged. They proceeded cautiously toward the merchant's villa. The whole building had been burned and pillaged. A wounded servant told them the merchant had been killed two days ago by another of his servant, with a dagger, which the PCs recognised as typical of the Yuan-Ti. Save for the rogue, no PC had the guts to ask for its payment, considering the merchant had already given them a very generous advance.
When they exited the village, the PCs were accosted by a street urchin who showed them a similar dagger. The urchin explained he had been paid to show it to the PCs and tell them that each of them would receive such a dagger. It was a clear warning about meddling with the Snake People.
The wild elf had offered them to guide them to the Cradle of Humanity, the most populous regious, by elf paths. It would permit the PCs to avoid encounters with the Iron Hounds slavers who controlled a part of the main road to the Cradle of Humanity. The PC gladly accepted.
One night, when the group was camping in elven ruins. A sinister grey-face elf came to them. The ranger/rogue PC had already saw him several months ago in a caravanserail in the Ruthless Desert, trying to assassinate another elf. The grey elf explains he wished no confrontation with the PCs, explaining he had come for the wild elf. The party banded together with their elven friend. The sinister grey elf departed. but came back later in the night with several ghost-like fey hounds.
The party killed the sinister elf, but the wild elf had been seriously wounded. The paladin NPC explained that the problem lay not with the body but the soul. The wild elf asked them to bing her to a glade about two days from their camp. The PCs did, but one by one, became lost in the forest until only the wild elf, the ranger/rogue and the minotaur barbarian remained. Surrounded by crows, a young girl with monstrous traits welcomed them and accepted to save the wild elf, but explained one PC had to pay a terrible price: he would have to renounce to what is due to him. The ranger/rogue accepted. The elf's dying soul was fused to his own, which caused him great pain. When he woke up, his hands were clutching the elven cloak and he fell different, having became something like the first half-elf from the Savage Wilderlands (my homebrew world).