Ooze Rancher

From the introduction:

This adventure can be can be easily customized to a party of any size or level, or run as a level 4 adventure for 5 players. It can work as a small side adventure in an existing campaign, as a standalone one-shot, or the start of a new adventure. Use the links to the tools in their relevant section to customize the adventure to your party.

The party comes across a mage tower with dead bodies everywhere, all skeletons and no blood. A DC 12 Medicine check can determine that the skeletons are very fresh despite having no flesh. Further up the tower there's some lights on in the windows, and distant sounds of a scuffle and movement.