"The cure works, and Oliver and his team must escape their hideout when Slade's men arrive. Back at Verdant, Sara arrives with Nyssa and the League of Assassins to provide backup to take out Slade's men. Equipped with the cure, the team confront Slade and Isabel at Queen Consolidated. In flashbacks, Anatoli fires a torpedo into the Amazo, causing it to sink. During the destruction, Oliver presumably kills Slade, and Sara disappears overboard."
If I had to describe the Arrow finale in one word... I couldn't. It'd be two words, and they would be "holy shit". It took me a few times rewatching it to be able to look at it objectively, but at a bare minimum, I would say it was completely satisfying.
This finale saw an army of Mirakuru-enhanced soldiers, Roy taking up the gear to be Red Arrow (or maybe Arsenal), the LEAGUE OF ASSASSINS being all badass, and even Laurel got to be awesome in this episode. For the most part, death was avoided on Oliver's orders, but there were a lot of potentially-lethal scenes with Mirakuru cure-filled injection arrows.
Arrow has continued to be a realistic take on costumed vigilantes, with Oliver's speech at the end pointing out on an almost meta level that the slow approach has been the reason for the show's success. In his speech to an imprisoned and depowered Slade, Oliver talks about how Slade helped him become a killer when he needed to be one. Now, through his attempts to destroy Starling City, Slade has helped him become the thing that Starling really needs: a hero.
Despite fan speculation to the contrary, Sara survived the episode. Considering that writers heavily implied early on that Laurel would eventually become Black Canary, everyone was assuming she would die. Instead, she sailed off with Nyssa to a semi-happy assassin-y life while the true casualty of the episode dropped to the ground on the docks; Detective Quentin Lance's survival through next season doesn't look any better than Isabel Rochev's -- and her neck was snapped by Nyssa.
I wouldn't be surprised to see season three opening with (or a few weeks after) Detective Lance's funeral, and that is what provokes Laurel to start training with Oliver and Roy, taking the steps to become Black Canary at some point during the season. Katie Cassidy proved in Supernatural that she could be a badass as the original demon Ruby, and I am looking forward to seeing her journey from here on out. If it does come at the cost of her dad, I'll be disappointed since the actor has grown on me, but I can definitely see how it would spin out from there.
The real standout for me in this episode was the fight between Oliver and Slade, although "fights" might be more accurate. Throughout the episode, tension builds in both the present day and flashbacks, erupting in the fights between Oliver and Slade. As it goes on, they cut back and forth between the two fights, and... wow. I was so into it that it took until the second rewatch for me to actually think objectively about the editing on the fight.
How did you feel about the Arrow finale? Love it with me!