DND 5e one shot: legally distinct Goonies

The Goonies movie is basically a DND session, you have a map, pirate treasure, caves to crawl through, so you can do all sorts of fun things with the basic plot. I decided to have fungus zombies since my party had reached level 9 and it's hard to make a good threat, so opponents with a danger that bypasses AC seemed good.

We have a guild set up so it was easy to have the guards come ask for help like we're the A-Team or Ghostbusters, whatever works for you, just say something like this.

One of the city guards that hands quests to your guild says: “Recently we’ve caught some pirates stealing explosives. North along the coast is a sea cave where the pirates smuggle in their booty. It seems they have a ship trapped in there by falling rocks, hence the need for more explosives. We’re sure most of the pirates have left the cave to get supplies, but we also know those caves tend to attract monsters. Sounds like your kind of job! The reward is five gold for the head of each pirate you bring back, attached to them or not. The ship’s owners will pay a reward of 100 gold to get it back INTACT. If there is any cargo with no clear owner we'll auction off and you'll get a generous split.”

What happens along the way is your choice, we started an hour late so I just teleported them to the cave, but if you have some fun ideas for wilderness go ahead and do that. It would be easy to have one session for travel shenanigans, then another one or two in the caves if you meet up often enough, but we keep getting interrupted so my goal was 4 hours of playtime.

Soon you reach an area of rugged hills covered in dense forest near coastal cliffs. After a short hike you find a small cave. At the back are two doors. One seems to be the main entrance, but it's been exploded, with some gore around. The other has warning signs around, and the door has been bashed out by some monster that shuffled off into the wilderness! Inside it is dank and narrow, with glowing mushrooms in the distant depths.

Encourage rolling checks for investigation and nature so they'll get hyped up about the danger. My party spent so long debating I rolled to see if a wandering monster would get them! But the lure or a ship load of treasure drove them in!

You descend into the dark depths, a winding wet passage that soon opens into a cave about thirty feet wide and fifty long. It's all mushrooms, glowing green on the walls, and purple tentacles slithering on the floor. You see two humanoid figures beckoning you!

Have them roll skill checks to see these are zombie pirates under the control of the fungus hive mind. The cave here is a trap to catch and devour any animals that wander inside!

I intended this to be the appetizer course, to see how the party handles weak but infectious monsters. I only had a few in this room.

Oh, also I had my own PC in this fight but then forgot they existed the rest of the session lmao.

You go down a narrow, dank passage with swaying, shimmering fungus. The stream trickles across the floor, and scattered bones that crunch underfoot.

The next room I just had some hazards planned like infectious spores!

The next corridor is fungus free, and has a carved channel for the stream. You easily walk down it into the sea cave! Over a hundred feet wide, plenty of room for the still floating SLOOP, a small fast raiding vessel with one mast that is about 20 feet tall. Deck is about 60 feet long and 30 at the widest. A dozen cannon and a crew of 90. There is a rickety dock for boarding. Fungal tendrils and mushrooms cover the wood! As you walk on deck, you see more corpses. They are around a table with an unfinished poker game, with gems and coins piled up. There are five barrels of rum (@42 gallons each) loosely lashed to the deck. Several others have been drained by the partying pirates. The corpses stand up!

Note: my brain said cutlass sounds like a pirate sword, and I think originally this was based on some third party scimitar, maybe!?!?! but I forgot where I saw it, or why I even picked it other than most people go for fire resistance. Whoops! Always make notes about sources so you can double check!

Inside the Captain's chest is:
1 small sack of nice jewels [500 gold]
1 scroll of control water.
1 potion of water breathing.
1 ring of water walk.
You also find the ship’s log detailing events of zombie outbreak. the pirates got bored waiting and got drunk and went into the wrong door!

The cargo hold has a large amount of canvas sacks and two large chests, padlocked shut! As you open, you look at a pile of pure dark chocolate. Runes inside keep the interior ice cold. Behind, the sacks all say “PURE CANE SUGAR”.
To one side is the inventory log, which states that they have:
Sugar, 2 tons. [I estimated this as 1 gold per pound = 2240 gold per ton ]
Chocolate, 300 pounds. [ 2 gold per pound = 600 total ]
And then limes and hardtack and such.
Since you’ve cleared the area it’s safe to short rest.

Now the party can use the explosives to clear the rubble, use as much detail as you need, I just said they succeeded since it was getting late IRL. Then sail it back to town, the current and winds will help. Challenge- if need to add time, roll dexterity or strength to steer the boat. A crit fail will make a rum barrel roll off the deck! Back at the docks the port authority examines the ship which the owner reclaims. But the cargo has no claim on it and will be sold off, the baking guild will take the sugar and chocolate, and after port fees are deducted your party can split the profit. You can let them haggle to get a better share!

I also have an optional NPC, it depends on if it would help low level party or be a bother to have a DM PC, but yes I made an ogre that was chained up by the nasty pirates to be their guard dog, and if you bribe him with some chocolate on the table nearby he'll go clear the main entrance and go home, or help smash through the zombies if needed.