Chapter 789 is titled "Lucy!!"
At the walls of the Birdcage, Riku and Tank begin assisting the citizens in slowing it down. Elsewhere, Doflamingo immobilizes Viola and takes control of Rebecca, forcing her to attack her aunt. In the middle of it all, Gatz gives an announcement to the entire island, revealing how "Lucy" was actually Luffy, giving hope that Doflamingo would finally be defeated with one hit once Luffy shortly regains his Haki. With a few seconds left, Doflamingo impales Gatz and prepares to make Rebecca deliver the killing blow. Before she could bring her sword down on Viola, Luffy arrives and intercepts Rebecca's blow, breaking her sword, and Law frees Viola. With his Haki recovered, Luffy prepares to finish his duel with Doflamingo.
The people of Dressrosa continue pushing the Birdcage as it reaches the King's Plateau and begins breaking it. Riku Doldo III and Tank Lepanto rush over to the SMILE Factory and assist the people in pushing it, and Riku commends everyone for helping save Dressrosa. This gives the people more spirit as they continue pushing.
Elsewhere, Rebecca screams at Viola to stop attacking Doflamingo for fear of her aunt's life. Viola does a roundhouse kick on Doflamingo, but he easily blocks it and states that he would not hesitate to kill Viola despite her once being a Donquixote Pirate. Doflamingo then immobilizes Viola and takes control of Rebecca, ordering her to kill Viola. Rebecca heads toward Viola against her will, both of them imploring Doflamingo to stop.
The citizens continue running from the Birdcage, but it has shrunk so much that there is nowhere left to go. The Colosseum gladiators continue pushing on Bartolomeo's barrier, and Kyros wonders where Rebecca is. Right then, Gatz activates a Den Den Mushi and broadcasts himself across Dressrosa. The citizens become shocked when they hear him and try to find out why he is broadcasting, but Gatz continues, reminding everyone of the star of that day's Corrida Colosseum tournament. Cavendish listens intently, when he suddenly realizes that Law is gone. Gatz then lists the accomplishments of the aforementioned star, and everyone realizes that he is talking about "Lucy". As Rebecca begs Lucy for help, Gatz reveals to everyone that Lucy was Monkey D. Luffy, which shocks them.
Gatz then recalls the Donquixote Pirates' takeover of Dressrosa ten years ago by controlling Riku, and tells everyone that Luffy has promised to knock out Doflamingo in one blow. This causes the citizens to cheer, and Gatz taunts Doflamingo, calling him a false king and telling him that Dressrosa would be his execution ground. Gatz then yells that it will only be ten seconds before Luffy comes back. Meanwhile, Hajrudin succumbs to his injuries and falls as the effects of the Teardelions wear off, followed soon by Dagama and Ideo. Mansherry cries in regret for giving them false hope, but Kabu reassures her that she has saved many lives with her powers.
With Gatz's encouragement, the gladiators who are still standing continue pushing and the citizens cheer on Luffy. Doflamingo finally reaches the end of his patience, however, and stabs Gatz using a sheet of string. The countdown finally reaches zero as Gatz falls, reiterating his trust that Luffy would defeat Doflamingo with one blow. Rebecca draws nearer to Viola, who tells her crying niece that she would not hate her for this and that she did nothing wrong. As Rebecca prepares to deal the blow to Viola, Viola silently apologizes. Suddenly, Law uses ROOM to switch Luffy with Viola. Luffy intercepts Rebecca's sword with his forehead, which is covered in Busoshoku Haki, breaking it as a result. Law then frees Viola as Doflamingo cries out Luffy's name. Gatz then announces to the citizens that Luffy has returned, as they cheer at Luffy's arrival as Luffy and Doflamingo stand off once again.
- Riku Doldo III and Tank Lepanto join with the people in pushing back the Birdcage.
- The effects of Mansherry's power are starting to wear off and she cannot heal the same person a second time.
- Doflamingo easily injures Viola and forces Rebecca to try to kill her.
- Doflamingo impales Gatz with his powers.
- Luffy recovers his Haki and teleports to Doflamingo's position via Law's power, saving both Viola and Rebecca.