I wanted to address a question that has come up from more than one person about the alpha testing of Lone Spelunker, namely this:
People have been commenting that the oxygen level drops too slow for it to be a challenge to drown in the caves.
For the most part, this is true. When you encounter water in the game, it is often confined to one or two pools, or very shallow in size. This doesn't present a drowning risk to any but the most careless of spelunkers.
The conception is that you have access to a small scuba tank, so the oxygen meter goes down very slowly. For most cases, that's overkill; you wouldn't need a scuba tank to explore a backyard swimming pool, for instance.
However, one of the things that the cave generator can do is set an "aquifer level", which causes all of the cave's passages and caverns to be flooded with water below a certain level. For instance, I just fired up the "random massive cave", and here's a map of the cave it generated:
As you can see, more than half the cave is underwater. The early pools in the "dry" parts above are no challenge for diving, but you'll quickly find yourself needing to do some oxygen caching in the lower parts of this cave.
However, maybe what this feedback indicates is that - perhaps - I need to make a distinction between "free diving" and scuba diving, and require the player to put on a scuba outfit before going into the deeper areas of the water-filled caverns, while still having the breath meter drain quickly when free diving.
This would be a natural extension of the "free climbing versus using ropes" approach. I'll have to think about the ramifications of this on gameplay.
But in the mean time, happy spelunking.