I have tinkered and homebrewed extensively to produce hardcore/grimdark style games, and I think 5e hardcore mode hits on all the notes I've found important. Not only that, it works right out of the box to produce the game style I am looking for. DMs, save yourselves hours of work on homebrewing your own gritty rules and just buy this product. Either using it as a jump off point or implementing the entire thing verbatim, you will not regret it if you want a more hardcore 5e experience