Seven Trumpets 6.2:Dragon -> Earth

The first angel sounded his trumpet, there came hail and fire mixed with blood, and it was hurled down upon the earth. A third of the earth was burned up, a third of the trees were burned up, and all the green grass was burned up
And it’s one for the hail of fire that bleeds
That sounds apocalyptic. 

But it might be possible to dull down the trumpet judgments a bit and treat them as metaphors for the idea of atonement - the darkest hour of Israel’s existence – the Great Tribulation - and its redemption on the Day of the Lord. On that day, God’s intervenes by sending a messiah who rescues Jerusalem from the armies encamped about it and then rules the earth from the throne of David.
Two for the mountain hurled down into the sea
Three for Lucifer in the rivers made grim
There are a couple of rather mysterious references in the Old Testament to some exalted presence being expelled from heaven. The most quoted one comes from a prophecy of doom for Babylon by the prophet Isaiah (chapter 14:14-19 – Babylon is often treated as a metaphor for Satan by the Old Testament prophets)
How you have fallen from heaven, 
       O morning star, son of the dawn! 
       You have been cast down to the earth, 
       you who once laid low the nations! 
...the man who made the world a desert, 
       who overthrew its cities 
       and would not let his captives go home?" 
...But you are cast out of your tomb 
       like a rejected branch;
There is another similar reference in Ezekiel to the King of Tyre (chapter 28:1-19)

" 'In the pride of your heart 
       you say, "I am a god; 
       I sit on the throne of a god 
       in the heart of the seas." 
       But you are a man and not a god, 
       though you think you are as wise as a god. 
... By your great skill in trading 
       you have increased your wealth, 
       and because of your wealth 
       your heart has grown proud. 
 ...Will you then say, "I am a god," 
       in the presence of those who kill you? 
       You will be but a man, not a god, 
       in the hands of those who slay you. 
 ...The word of the LORD came to me:  "Son of man, take up a lament concerning the king of Tyre and say to him: 'This is what the Sovereign LORD says: 
       " 'You were the model of perfection, 
       full of wisdom and perfect in beauty. 
 You were in Eden, 
       the garden of God; 

They are pretty fleeting references, but that has not stopped scholars and poets (such as John Milton back in 1667 in his poem, Paradise Lost), from building a mythical narrative around the idea of Satan being demoted from chief among the angels to perverted corrupter of mankind who has been exiled from heaven. 
Satan, the Devil, the Evil Emperor or those who act in the spirit of such malevolent forces, may be the agents polluting the seas and the rivers and making life very difficult for mankind. 
The image of the fall of Satan might be an example of the Hebrew writers taking familiar pagan creation myths about wars among the gods and subverting them to make it easier to explain their conception of a monotheistic religion. 
As I have mentioned a few times, Jesus said he came to fulfil the Law of Moses (and the Prophets). 
Ask any observant Jew what is the cornerstone of the Law of Moses and he will quote Deuteronomy chapter 6 verse 4 –
the Lord our God is ONE GOD.

It is possible that when writing down the words of the bible, the scribes wished to argue the case for monotheism – ONE GOD. 
To do this, they may well have taken aspects of the polytheistic (many gods) myths of their neighbours and turned them on their head. 
In other words, to annunciate their radical notion that there is only one God, they may have subverted the pagan myths about wars among the gods, often featuring dragon like creatures as warriors and defeated gods being expelled from the abode of the victorious gods. 
They may have recycled them into their explanation of the world, the universe and the meaning of life in which there is only one God.
Jews, Muslims, and people who think about the statement, “The Lord your God is one God” proclaim the importance of monotheism. 

They do have some justification when they suggest that Constantine and the church fathers who sided with the bishop of Rome turned the “Christian” church into a kind of idolatrous religion worshipping many gods (Father, Son, Holy Spirit, Mary, the saints) that is condemned by God.  

The second angel sounded his trumpet, and something like a huge mountain, all ablaze, was thrown into the sea. A third of the sea turned into blood, a third of the living creatures in the sea died, and a third of the ships were destroyed. 
The third angel sounded his trumpet, and a great star, blazing like a torch, fell from the sky on a third of the rivers and on the springs of water— the name of the star is Wormwood A third of the waters turned bitter, and many people died from the waters that had become bitter.
So much for Satan – now for Israel..
And its one for the hail of fire that bleeds
Two for the mountain hurled down into the sea
Three for Lucifer in the rivers made grim

Burning Hail, Mountain in Sea, Lucifer in River