Trail of the Hungering Dead, an adventure for 14th-level characters, is now up on the DM's Guild.
I test-ran it here on the forums in a PBP game.

Spoiler: description
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Do you want your players to feel like they are in a zombie movie, struggling against a deadly horde that tries to surround them, overpower them, and bear them down to the ground to be devoured? This is an adventure that can threaten even the stoutest of characters, and is not recommended for parties of levels 12 or below unless they are larger than normal.

This module is designed to take 4-8 hours of play and cover a single day, depending on the party’s speed of play and how thoroughly they decide to explore. It includes suggestions and some plot hooks that can be used to tie this easily into a variety of long-running campaigns, or it can be run as an indepdent adventure.

The players will come upon a sacked town, figure out what happened, track an item whose theft has ominious implications for the region, and explore a partly-flooded old temple to end the threat.

It's primarily combat-focused, but there are a few areas where exploration and route choice makes a difference, as well as traps if the party goes for the optional temple treasury.

The antagonists in this module are mostly ghasts and ghouls, but the module title and cover page are deliberately selected to not spoil this. These are greater ghouls and ghasts that can challenge higher-level characters, backed up by mobs of lesser ghouls that can surround, paralyze, and devour the weak and unlucky, led by a Warlord who can disrupt the tactics of living foes.