Wonderball

The way you save the game is to walk toward one of the black flowers that grow on the wall with the mist surrounding it and hit "X" to touch the flower.
When it asks you if you're sure select yes.
These do not damage you, your characters will fall to the ground and pass out, but the black screen will just fade to the save screen.
The flowers are not and obstacle or a trap, they're save points and completely harmless.