You can typically find and download these types of mods through platforms like Patreon (for Zero's Sims 4 Mods) or Mod The Sims .
Based on your query, it seems you are referring to the mod for The Sims 4 (often associated with modders like Zero or similar creators). This mod enhances the vampire gameplay experience in The Sims 4 by making vampire behavior more dangerous and lethal to human Sims. VAMPIRES - Can Kill
Ensure you have the required XML Injector downloaded and updated to make the mod functions work in-game. You can typically find and download these types
Some versions of these mods allow for the enabling/disabling of "extreme violence," allowing you to tailor how often Sims kill each other. Ensure you have the required XML Injector downloaded
Turning a Sim into a vampire can now have a chance of failure, resulting in death during the transformation process.