Tyrus was like an ancient New York or London, with people and goods coming from all over the world. And then god god pissed off and decided to destroy it for all time. Oddly, Republican politicians never seem to mention this passage when they talk about god as the original free marketeer.
Like many a powerful mayor before him, the mayor of Tyrus thinks of himself as a god. So the real god decides to cast him down into the pit (v. 8), where they will die the deaths of the uncircumcised (v. 10) whatever that means.
And now a very confusing episode in verse 13, which informs us that the mayor of Tyrus spent some time in Eden? Apparently this is meant to be ironic, a quality the bible is not exactly strong on. Smiting, yes. Speaking of which, god then gets around to detailing all the ways he's going to punish the city for its arrogance. Show, god, don't tell.
God is going to make the Egyptian Pharaoh choke to death on a fish bone, which I've always been terrified of. Then he's going to feed him to the beasts and birds. Then he'll do lots of other bad stuff and give the country over to the Babylonians.