Ultimately, everyone must make a purchasing decision for themselves. If you love Against the Storm and simply want to add some more spice to your runs, because you already know every cornerstone and event like the back of your hand, then Keepers of the Stone is a no-brainer for you – it brings a variety of new content, a slight increase in challenge, and minimal mechanical add-ons that will feel impactful to someone who plays the game a lot. If you’re new to the game anyway, then you’ll be completely fine without the added investment into the DLC for a long, long while.