If your feeling of dread rises off the chart, it's time to head back to safety.
You will know when you swim too far off the map into the Void if it gets really dark and the background music stops playing.
The one exception is Fevered Peppers, which can regrow after you leave the area. Swim and Seaglide speeds have been reduced, and there is no Cyclops or Seamoth. You can relax and take as long as you want to complete the game.
