Adventure 1: Drive the witch Baba Yaga from a forested barony.
Adventure 2: Stop an evil vizier from summoning a powerful, evil djinn.
Adventure 3: a secret cabal of demons from staring a war between two jungle tribes
Adventure 4: Keep the now vampiric vizier (from #2) from summoning Cthulhu (more or less)
Adventure 5: Save an island kingdom from an awakened Great Red Wyrm dragon.
The Island Kingdom was once unified. It was ruled by the descendant of the first king who colonized the Dragon Island by subjugating the namesake dragon, allowing people to colonize the islands (northernmost island has a climate like Taiwan -- so you can have a forested island in the north --, southernmost like Luzon -- so you can have jungles). Eventually it was separated when the last king had two heirs and split the Northern and Southern parts of the archipelago between them. Peace endured as family bonds were still strong, but recently the situation worsened after years of very bad agricultural situation, engineered by a cabal of demons who want to make people starve so they turn to worship them for food, as they'd appear as saviours of the land (no more magical power to divert to make the land barren, more worshipers, profit!). The tensions between the North and South are rising as food is becoming scarcer each year -- rice fields are turning into desert over the last decade... (hello desert!) -- and competition for the fishing grounds leads to episodic fightings between the once-pacificistic island neighbours. Theis is the result of the Climate Curse laid by the Cabal. The tension are exacerbated by a relative lack of leadership, as both kingdom have underage rulers : in the North, a vizir is in charge, with a nominal "wise men council" advising him, as the prince is 17 years old, and in the South, the clan leaders are forming a governing council while they wait for the crowning of their 17 years old princess next year.
Act I : The demons empower a witch by granting her dark knowledge in order to make the last game-rich forest a no-go zone, in the northernmost part of the North Kingdom (the one whose main farmland is slowly turning into a desert). As harvest was bad, its vital to supplement food by hunting and gathering and shippping food to the rest of the kingdom. The PCs are tasked to convince the hunter-gatherer to resume work and hunt more than necessary for just their own families. It will take countering the witch. Of course, she was once a lowly rural magic user and the cabal of demons provided her with dark knowledge to empower her. After arresting her, the authorities seize the evil books of dark knowledge she had.
Act II : Despite food production from the northernmost forested island resuming and saving the North from starvation during the winter, the situation is still bad. The vizir from the Northern Kingdom uses the dark knowledge (he read the books the PC brought back) to seize power and try to summon an evil djinn to wipe out the southern population. More land = more food. He'll be seen as a saviour and no-one will question his legitimacy when eventually he'll assassinate the rightful young prince. The PC stops him, and learn about the Evil Cabal (and possibly destroy the books of unspeakable knowledge).
Act III : The tensions keeps rising as the cabal enginneers more and more incidents. The PC try and defuse the tensions at the court but it looks like it's inevitable that war will follow. Especially since some in the Southern Kingdom are rather irritated of the late vizir plans of wiping them out with the aid of an evil djinn. The northern prince (who assumed power directly despite his young age after the former vizir failure) send the PC for a diplomatic mission. He's also interested in marrying his (distant) cousin, the young princess of the southern kingdom, because they are madly in love and the political advisor say it would boost GDP. The PC arrive in the Southern Kingdom, also forested but by a jungle because it's more southernly and tropical (and they don't suffer from the Climate Curse). Problem, the biggest of the clans of the kingdom has seceded, claiming the princess is unfit to rule because she wants to marry the northern prince whose kingdom planned to wipe them all. They will see no reason, and tensions are escalating threatening a civil war, as they don't want to relinquish the regalia needed for the crowning of the princess. Of course the Evil Cabal is behind that: they don't want the Southerner to intervene. Fortunately, the PC defuse the tensions. And they end up reconciling everyone and bring the answer from the princesss back to their prince...
Act IV : Unfortunately, back home, undead vizir is back in power. The general population quite liked the idea of wiping out the Southern Kingdom to get more arable land, and thinks their prince is too young to be really in charge and he should let the grown ups make important decision. When the Evil Vizir assumed regency once more, they didn't immediately revolt, and adopted the worship of the Evil Cabal as the official religion, turning the kingdom into a quite "Strahd-like" place (with desert). He's now actively trying to summon Cthulhu instead of a djinn because he was taught even better rituals while he was dead. Hum, "in exile". The PC intervene, stop him, restore the young prince AGAIN, marry him to the young princess, outlaw the worshipping of the Evil Cabal. Everything is good again.
Act V. The Cabal sees their plans sabotaged. They off the newlyweds out of spite and eat their souls [no cheap Raise Dead spells here, PCs!) and leave, because they have better things to do and other places in the multiverse to subvert. The Climate curse ends with their departure (mana is not cheap!) A new ruler will need to be chosen, and as part of the trials to select a new fitting king, they release the dragon, who apparently was only bound by the terms of his surrender to obey the first king and his legitimate heirs after him. The PC are left to clean the mess, subjugate the dragons, are chosen to rule the reunited kingdom.
It could be an adventure for level 5 to 13, with the final fight against an adult red dragon balanced for a party of 5-6 PCs at this level. With the PC starting at level 5, they have a reason to be already "local heroes" to be tasked by a member of the advising council to the vizir with the initial, vital, mission, as the vizir can be presented as bellicose and intent to go to war with the Southern Kingdom in the first place, while the advisor tasks knights from the court to resolve the forest strike situation to help quench popular support to a war.
As a follow-up adventure, you could have the PCs taking revenge on the Cabal.
Hope this helps and respect the constraint (5 adventure as stated, keeping exotic locales in a single cohesive thread).
