Love the concept. When that first tide came rolling, I was scrambling to find safety (and almost drowned in the process). Definitely a success on invoking a sense of impending doom. The "elevation" of the tiles is also pretty cool, you can kinda plan around a bit. Has great potential :)
Anyway, on to the feedback:
1. Combat is very difficult and it's basically impossible for me to land a first hit on something. Basically the only reason why I didn't progress further. I'll prolly come back to it some more these days to see if I can git gud :D
2. Some pointer to your house and/or minimap would be nice. At least in my opinion. Maybe the absence of it is deliberate from a gameplay perspective, but I get lost pretty quickly, especially when the tide is changing things. I'd rather get cut off from my home because I was too greedy and now there's a bunch of water between, than not being able to find it. If you would add a minimap, it could show elevation, so you could also plan things better - it would maybe add another gameplay element.
3. I noticed you lose a heart the second you enter deep water and then you lose it every x seconds. I'd maybe try that you don't lose it immediately, but that you start that "timer" and only when you remain in the water for the timer duration, you lose a health point (and ofc keep losing it while you remain in the water). Basically, you don't punish the player immediately, but give them a small window to correct their mistake. You still slow them down like you do now, so you don't get players trying to swim across. If someone gets walled off by water, that extra second or two won't mean much.