All's been said, but I have to write something so I can add another 5 stars for this. Thanks pal, that was a great trip.

There's a very annoying ISH over the whole flash. But I actually liked the story, even with the very basic animation. So it's a pass.

The lung volume starts rising again when the whale stays at 500 m depth, that's not physiologically correct imho. It would be nice to add the lungs themselves to the whale as well, so you can show them being pressed together by the water pressure on the body. Or add a balloon, you can easily model it's volume in function of the depth. That illustrates nicely what goes on. It's nice to add weights as well, symbolizing the pressureby the water column.

Do something about your screen size

Part of the game is unvisible due to the wrong screen size settings.

Very good

OK, I stumbled on this a bit late, as the game is more than two years old by now. The new one (Gemcraft Labyrinth) beats this one any time. Still, it is a very nice defence game, and a great precedessor to what is in my eyes the best tower defence game on the net. I've played a few rounds and enjoyed it, but I guess I'm more for the new one. It just offers quite a lot more, both in graphics and in gameplay. In this Gemcraft 0, you get random gems. In gemcraft 1, you can choose them and that makes a difference. Still, the random effect can be nice (and surprising), and Gemcraft 0 has more story to it than its follow-up game. A matter of taste if you ask me.