Free TTRPG Battlemap – Underwater Cavern
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prompt written for it.
The scent of the sea is sharp in your nostrils as you approach the docks of a large seaport. But, speaking to the harbormaster to book passage, you learn that all the vessels are landbound. She informs you that monstrously large sharks have been biting holes in their ships, and while there have been many expeditions to kill them, more keep turning up.
Needing passage and unsure what to do, you head to an inn for food and sleep. Inside, you are accosted by a short, balding man with a long, gray beard and a robe he often stumbles over. He explains, in a rather roundabout way, that he’s trying to pay adventurers to seal the cavern network the large sharks come from—but everyone’s been refusing!
You see, he’s a wizard who had a hypothesis that an ancient species of shark (believed to be extinct for millennia) had adapted to survive in warm, underwater tunnels. Everyone thought was mad, so to prove it he opened a hole in them; releasing a veritable torrent of sharks!
While initially he was rather excited to have his theory proven—dismissing years of cajoling from fellow academics—the highly aggressive sharks have since become quite the nuisance. They are, after all, destabilizing the ecosystem, preventing farmers from visiting their oyster farms or fishing, eating all the whales, attacking ships… etc, etc.
As the passage you seek is easiest by ship, you begrudgingly accept. The wizard insists on paying you with a bag of rainbow, supposedly magic jellybeans. He also emphasizes that he doesn’t want you to kill the sharks, just seal them away like before—where they can live in their own microcosm. The wizard then equips you with strange shoes, shaped like seal flippers, as well as three magical orbs to place around the first cavern which will collapse it when the word “Zimzalabim” is said. Lastly, he casts a spell that enables you to breathe and fight in the water as you would on land—though it only lasts for 24 hours.
Before you leave, a villager pulls you aside and discreetly offers a large bag of gold to destroy the sharks inside the cavern network instead. He’s seen the destruction they can do, and doesn’t trust that the blighters won’t escape again.
The ancient sharks are huge. But when you arrive at the entrance to the underwater caverns, you see that the ones inside are even larger—so large they couldn’t leave through the hole the wizard blasted. It appears to be a breeding ground, and a colossal shark is within the area that you’ll have to place the charges.
DM’S NOTES: The underwater cavern network is close to the surface as the sharks thrive in warm, shallow waters. The rocky ceiling is porous, so sunlight still filters down through much of it. The caverns themselves also contain ancient species of giant squid and other whales, which feed upon the smaller fish, shrimp, and—of course—each other.
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