The tone of it is that he seems calm about how he wants the world the end. I chose this because of his word selection. He states in the poem that he favors with who holds fire. Another one is that the destruction of ice is great.
The theme of the poem is fear because of him asking how the world will end. He said fire or ice . But in the next couple of lines he says that "I hold those who favors with fire". So he is saying that the world will in fire.
The poem is symbolizing how people show their emotions and their behavior