What caused this zombie plague?

[Laserlight]

Looking for inspiration on tying some threads together for my players--three players, about to be L4. Two new-to-D&D-players ( Human tempest cleric, halfling arcane trickster) and one very experienced player (Thri kreen battlemaster, although this isn't nearly as Dark Sun as Dark Sun)

The facts they know:

a) they're on an island with a village built at the foot of a mesa, and a temple (to a god with Trickery and Storm domains) carved into the mesa a couple hundred feet up. The top of the mesa is at least a hundred feet above the highest point of the temple.

b) a waterfall from the top of the mesa has been a water source for the village, but water stopped flowing a couple of weeks ago.

c) the PCs are currently fighting off raiders / pirates, the leader of whom got into the temple and stole a book.

d) several fallen pirates, and a few slain villagers, have turned into zombies.

I'm inclined to say that something arrived / appeared on the mesa which causes zombie-ism; the head priest recognized it and turned off the water to prevent the village from being infected, but some of the plague is getting through anyway. If the PCs turn the water back on, all the villagers they're saving from the pirates will become zombies.

What I'm stuck on is "what arrived / appeared and initiated the plague?" It doesn't necessarily need to be something the players can successfully fight). Right now my placeholder is "mutated plants / myconids /something on top of the mesa" but I'm not feeling it. Suggestions?

[Kurt Kurageous]

Water carried some bacteria that causes the 'disease' of zombism, symptoms only affecting the dead (like vampirism).

Yawn, I know. But that facts fit the situation.

[RolandDeschain]

Some god of undeath tricked the trickster god because....reasons(presumably some longstanding feud or grudge and what better way to get even than to trick the trickster).

The god of undeath rearranged some of the sacred texts so the clerical rites that converted the water gathered from the storms into holy water, instead turned it into unholy water that carries the zombie plague. Periodically the holy(storm) water is dumped into the river basin above the waterfall to carry the trickster/storm god's blessings to the village, and the head priest discovered that it was unholy zombie water too late but did eventually shut it off.

Perhaps even more troubling, though, is that the pirate leader now has the altered holy text and can presumably create unholy zombie water....what sort of zombie hordes will he raise if he gets away????

[Laserlight]

Water carried some bacteria that causes the 'disease' of zombism, symptoms only affecting the dead (like vampirism).

Yawn, I know. But that facts fit the situation.

Yep, but how did it get into the water? Until a couple of weeks ago, there was no problem. Did something come along and add zombie dust? Was the plague always there, but the head priest was dealing with it...until a couple of weeks ago?

[Segev]

A lich has set up shop nearby and the regional effect is already starting to animate zombies from the dead.

A death tyrant beholder is dreaming of a zombie apocalypse that killed it and made it undead.

A hidden plantation run by a powerful necromancer who died while adventuring three weeks ago has slipped its controls, and the undead are the former workforce of said plantation.

A powerful artifact causing a death curse was destroyed, but now he broken and half-devoured souls it contained are returning to the recently slain corpses.

A wicked and mischievous faerie is cursing people with partial invisibility and an inability to speak, leading to gem looking like corpses missing significant portions of their anatomies and moaning like the undead.

A wealthy local has contracted a witch doctor to imprison the local psychopomps until they each individually agree never to take him, this assuring his immortality. Until they’re released, noting that dies on the island can stay dead.

[Spo]

How about the "book" that was stolen by the pirate king was actually a magical seal that unleashed the curse which affects random recently deceased dead. Eventually the curse will grow in strength as it eventually claims bodies to the extent that it will start claiming the living too. That is why it was hidden on an uninhabited island in case the seal was broken, no one would be harmed.

Because the book/seal could not be destroyed, to was placed on an uninhabited island in a temple whose ancient mechanical and magical wards have been triggered or ruined by time. The village/settlement initiated itself after the mage who built the temple/vault for the seal/book had perished.

[Laserlight]

A wicked and mischievous faerie is cursing people with partial invisibility and an inability to speak, leading to gem looking like corpses missing significant portions of their anatomies and moaning like the undead.

That's wicked. That's definitely wicked.
:-)

[redwizard007]

It is said that in the time before my grandfather's grandfather, there was no river on this island. No temple. No town. Only a few fisherman, and even they always left before the season of storms. One day, so it is told, a mighty priest of the storm good sought shelter from his enemies in the barren, rocky coves. He had stolen a mighty tome from the temple of the god of life, and the agents of that powerful deity saw no humor in the theft. The priest knew that only his master could protect him from such a fierce adversary, so he began to fast, to pray, and to explore the island.

Guided by the divine, the old priest found a cavern, a gateway to the land of the dead. Deep into the cavern, he took the tome. Into the underworld, where the minions of the god of life would not go. Lo! The tome began to corrupt the very nature of the dead. Resting spirits woke and tried to return to families long perished. Bodies long buried rose and began to walk, looking for the warmth of life.

The god of death was not pleased. He cast his gaze upon the chaos in that corner of his realm, and caused the river of the dead to change it's course. The waters flooded through the tunnels. All they touched returned to rest. All but the priest clutching the Book of Life. As he tumbled through the water, the priest lost his grip on the tome. It whirled away, lost to the eyes of mortals and gods alike.

When he washed up on the sunny bank of the plateau above us, the priest was changed. Touched by both life and death, he could not die. He began to carve the cliff face into a great temple. For decades the man worked, carving, praying, fasting but never growing older. Sometimes he even remembered bits from the Book of Life, and wrote them from memory in a new tome in the temple.

Many years have passed since the priest completed his work. His temple to the god of storms was completed generations ago. Long before my people settled here, the priest dissappeared into the autumn storms that wrack the sea. When we found this island there was only the temple, the river and the jungle. Eventually, a new priest ascended the cliff and rekindled the sacred flames in the temple. That was many years ago. In the time of my grandfather's grandfather, or so it is said.

[Laserlight]

I'm tempted to just read that out to them verbatim. Thanks

[redwizard007]

I'm tempted to just read that out to them verbatim. Thanks

That's a hell of a complement. Thank you.

[Vogie]

Use a "Monkey's Paw" McGuffin
A small child who recently lost a family member to illness came across something that provides a wish, and wished that, effectively, "sick people didn't have to die".

Add some Be Careful What You Wish For rules-lawyering (or a Jerkass Genie), and you've got yourself a zombie plague