What is emptiness of annihilation? Some people because of inaccurate perception, thought that our human lives will end as we die. Just like blowing off the candle light, pouring hot soup onto the snow. It means that, once the light has been blown off, it won’t reignite; while nothing is left after the hot soup melted the snow. This kind of thought, only thinks about the current life, not the next life, as the good & evil, cause and effect of human life is thought non-existent, once a person dies, nothing is left, so what for doing good, while being evil doesn’t seem to be scary? Therefore this is called emptiness of annihilation.
However, even if the nature of dharma is emptiness, there is still manifestation, the karma we created, the distinction between good and evil, karma that applies to all. If you don’t do good, you will fall to the evil realm to suffer, which is also known as the emptiness of evil path.