Kingmak3r’s Most Highly Rated Third Party Adventures and One Shots

One Shot Wonders – A collection of 100+ stand-alone one-shot adventures.
One Shot Wonders Vol. II – A brand new sequel to the above.
The Corruption of Alder Glen – A folk horror adventure by D&D influencer Ginny Di and scenario designer JVC Parry.
Escape from Undergarden – Another adventure from JVC Parry, this one written with Benoit de Bernardy.
Dragon Relics – Another JVC Parry adventure. The giant king asks you to hunt down several relics to defeat his dragon nemesis.
The Lost City of Oren Bran – A popular dungeon crawl by the Eren Chronicles project through a ruined dwarven city.
The Carnival of Tears – Another Eren Chronicles adventure, a mysterious carnival comes to town bringing a dreadful secret.
The Delian Tomb – A well-known dungeon romp.
Drakkenheim: In Search of Smugglers – A D&D Beyond exclusive adventure set in the world of Drakkenheim.
Drakkenheim: Terror in Tierhaven – An introductory adventure to Drakkenheim.
Drakkenheim: Horror of Ashbay – A Drakkenheim interlude adventure.
Drakkenheim: The Blood of Kesselhome – A Drakkenheim dungeon crawl.
Grim Hollow: Citadel of the Unseen Sun – A collection of six scenarios set in the world of Grim Hollow, which together comprise Season One of their Fables adventure series.
Grim Hollow: The Grim Hunt – A trilogy of Grim Hollow scenarios in the Grim Hunt narrative arc.
The Wild Sheep Chase – A quirky adventure trying to restore the victim of a Polymorph spell.
The Secrets of Skyhorn Lighthouse – A nautical mystery with sea monsters.
The Corruption of Skyhorn Lighthouse – A sequel with more nautical mystery and sea monsters.
The Lamenting Lighthouse – A nautical horror adventure.
Shore of Dreams – A search for pirate treasure with a little east Asian flair.
The Mountains of Kam’Arag & the Eternal Frost – A quest through frozen peaks to unlock a sealed magical gate.
The Ghost and the Peddler – A Goblin Stone adventure. Is a traveling apothecary haunted by his father’s ghost?
The Chapel on the Cliffs – A folk horror adventure by Goblin Stone.
The Butcher of Alcross – Another popular folk horror adventure by Goblin Stone.
Harper’s Tale – Heroes seek to counteract a plague. Designed by a young girl with cancer and her father.
Tail of the Wyvern – An adventure set in Cormyr plus some Cormyr sourcebook material.
Burning Goblins – A goblin raid on a village. Doesn’t appear to be available any longer.
A Little Bit of Thievery – A heist to steal an item at a noble’s party.
The Wolves of Welton – A village is ravaged by a pack of wolves.
Ravenhome’s Plight – A village is ravaged by hordes of rats.
Of Conks and Cons – A grotesque tree is grown from an enchanted potato.
The Soulmonger – Devils besiege a village to try to steal the villagers’ souls.
The Tower Golem – A dungeon crawl through Logrimm’s Tower.
A Walk in the Spirit Realm – Something is wrong in the spirit realm where orcish ancestors test young warriors.
Annihilation Hold – A dungeon crawl through a mountain vault where ancient orcs imprisoned an evil djinni.
Madness of the Rat King – A romp through a mad alchemist’s lair.
The Heist at Nimressa – Breaking into a fort to steal a baroness’ treasure.
In the Heart of the Forest – A search for a lost druid.
The Proving Glade – Another forest adventure.
A Murder in Mossbank – A “whodunnit” style murder mystery.
Murder at the Old Wolf Inn – Another murder mystery.
Moon Over Greymoor – A village murder mystery.
The Horror of Ashwood Crypt – A horror-filled dungeon crawl.
A Night of Masks and Monsters – A mystery at a masque ball.
Rise of the Redscales – A one-shot for an all-kobold party.
A Dragon’s Breath – An ancient dragon wants to mend his relationship with an old friend.
Struggle in Three Horn Valley – A challenging island adventure.
The Hound of Cabell Manor – A mystery akin to “Hound of the Baskervilles.”

Kingmaker’s List of Top-Rated Third Party 5e Campaign Expansion Scenarios
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Scarab of Death – A cursed artifact is stolen in Waterdeep. Chaos ensues.
Waterdeep: Blue Alley – An additional adventure for Waterdeep: Dragon Heist.
The Purple Palace Heist – A heist side quest for Waterdeep: Dragon Heist.
Tyranny of Phandelver: The Rise of Tiamat – An adventure linking Lost Mine of Phandelver with Tyranny of Dragons.
Baldur’s Gate: The Fall of Elturel – An introductory adventure for Descent into Avernus or Tyranny of Dragons.
Baldur’s Gate: The Vault of Marvels – A Baldur’s Gate dungeon crawl.
The Imminent Light – A side quest for Descent into Avernus.
Shield of the Hidden Lord – A dungeon crawl beneath Baldur’s Gate to run with Descent into Avernus.
Candlekeep Murders: The Deadwinter Prophecy – A murder mystery set in Candlekeep.
Candlekeep: Curse on Beregost – An additional adventure to run alongside the rest of Candlekeep Mysteries.
The Cage – A trinket is stolen from an estate in Beregost.
Murder in Thay – An expansion adventure based on the “Mission to Thay” chapter in Tyranny of Dragons.
The Blizzard of Axe and Sword – An epic adventure designed to be played alongside Storm King’s Thunder or Rime of the Frostmaiden.
The Hunter in the Tempest – An adventure in the frozen north designed to be played with Rime of the Frostmaiden.
Revel’s End: Prison Break – A prison break adventure made to be run with Rime of the Frostmaiden.
Frozen Offerings – A side adventure set in Icewind Dale.
Stars Over Stormwreck – A continuation of Dragons of Stormwreck Isle that could be used to link to Spelljammer: Light of Xaryxis.
Banquet of the Damned – A folk horror adventure taking place just after Princes of the Apocalypse.
Storm King’s Barrows – Ten dungeon adventures made to be played with Storm King’s Thunder.
Escape From Riedra – A stand-alone adventure set in Eberron.
Murder on the Eberron Express – A murder on a lightning train in Eberron.
The Curious Case of the Calm Delilah – A horror adventure for Ghosts of Saltmarsh.
The Wedding at Ravenloft – An epic conclusion to Curse of Strahd.
Hunted! – A side quest for Storm King’s Thunder or Tales of the Yawning Portal where you chase a monster that’s slaughtering livestock.
Darkness Over Daggerford – An adventure for Storm King’s Thunder plus the Cromm’s Hold dungeon crawl.
Trouble in Wealdham – The party takes on a necromancer that is menacing a village.
Veratrem’s Tribal Siege – A green dragon leads an army of kobolds against Wealdham (see Trouble in Wealdham above), designed to be played with Storm King’s Thunder.
Volo’s Guide to Getting Murdered – A one-shot featuring Volo with multiple villains in the style of Waterdeep: Dragon Heist.
The Fall of Cyrog – A mind-flayer lair to be played with Out of the Abyss.
The Wizard of Zo – A side adventure set in Chult that fits with Tomb of Annihilation.
Dragonlance: Shadow of the Black Rose – An epic conclusion to Shadow of the Dragon Queen.
Dragonlance: Ispin’s Tale – An additional adventure for Shadow of the Dragon Queen.
Dragonlance: Seekers of Solace – A prologue to Shadow of the Dragon Queen.
Dragonlance: Prelude to War – Another prologue to Shadow of the Dragon Queen.
Dragonlance: Autumn Twilight – A 5e conversion to some classic Dragonlance adventures.
Dragonlance: Quest for the Horn of Kiri-Jolith – A side-quest for Shadow of the Dragon Queen.
Dragon Witch of Rashemen – An adventure based on Fizban’s Treasury of Dragons.
Black Water & Blue Wine – A shipment of wine goes awry in Neverwinter.
New Neverwinter: Jewel of the North – A Neverwinter sourcebook combined with a sandbox adventure throughout the city.
The Vault of Tomes – Dungeon crawl set in Neverwinter.
The Cloak Tower – Another dungeon crawl set in Neverwinter.
Escape from Shurrock – An adventure for Journeys Through the Radiant Citadel.
The Crucible – Escaping a Githyanki prison, could work well with Spelljammer or Radiant Citadel.
Vecna: Secrets of the Dead – A sequel to Vecna: Nest of the Eldritch Eye.
Trouble in Waterdeep – A free one-shot set in Waterdeep.
Visions of the Vault – Six short dungeons set following Trouble in Waterdeep. This no longer seems to be available though. Does anyone have this one?

Edit: Reddit Community Recommendations:
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Prepared! – A collection of over 30 one shot adventures by Kobold Press.
Quartershots: Roads & Ruins – 22 one session one shots for use when the party is travelling.
Quartershots: Lairs & Labyrinths – 22 one session one shots for use when the party is underground.
Quartershots: Woodlands & Waterfalls – 22 one session one shots for use when the party is in the wilds.
The Monsters Within – An adventure where the players are slowly turning into monsters.
Slayed on the Sandsailer – A murder mystery for the players to solve.
A Most Potent Brew – Slaying giant rats in the cellar.
Potions 11 – A witty magical heist set in Neverwinter.
The Beast of Graenseskov – A mystery set in Ravenloft.