How catastrophically bad is rod knock for your engine?

If you hear a knocking sound from the bowels of your engine, it could be rod knock, but what exactly is it, and just how catasrophic can it be?
Steel Horse Rides on MSN

Mechanics warn that ignoring these 6 sounds could lead to a total engine failure

Your car talks to you. Not in the "please take me to the beach" way, […] ...
The Daily Dot

‘Sounds like a brand new GM truck engine’: Mechanic reveals the engine noise you never want to hear—especially in a Hyundai or Kia. Then he reveals what you can do about it

If your Kia or Hyundai engine just started making a loud knocking sound, don’t panic. You might be eligible for a free engine replacement due to a massive engine recall. Featured Video A viral TikTok ...