Chapter 981 is titled "Joining the Fight".
Queen gives the Beasts Pirates permission to kill Luffy, Zoro, Kid, and Killer, and they are forced to run away from their onslaught, which even Hatcha of the Numbers joins in. Meanwhile, part of Kin'emon's group splits off to infiltrate Kaido's fortress in order to help surround Kaido as well as rescue Momonosuke. Elsewhere, the Big Mom Pirates attempt to scale the waterfall around Wano again, looking to find out why Big Mom and Kaido are in an alliance. However, they are knocked down by Marco, who is approaching Wano with Nekomamushi and Izo.
An attack from Kid is seen, with Apoo underneath and beaten up. The Beasts Pirates call onto Apoo and one of them recognises Kid, saying that he's 'Captain Kid' and is not one of them. They are surprised to find out that another member of the 'Worst Generation' has broken out of Udon Prison, and as such, Queen scolds and is told that 'all's well'. Kid then exclaims and grabs Apoo by the collar, furious that he got deceived by him then Apoo retorts that pirate alliances don't have happy endings. He then attacks Kid using his Devil Fruit ability but the latter smirks instead, saying that he's trash. The Beasts Pirates then asks if how can they take Kid alive during that situation, then Queen says it's okay to kill them. As the Beasts Pirates prepare to attack Kid, Killer defends from the back and Haccha proceeds by rampaging at the place. Another pirate pointed out that he already took out two people, in which Kid is surprised to find out that 'they can't control him'. Haccha gives a hearty laugh and the rampage continues, with Luffy's sillhouette being seen to attack. Luffy tells Kid to get to the keep and Kid proceeds. Luffy exclaims at Kid for acting on his own, Zoro then exclaims that he's one to talk, while Kid says the same to him, for Zoro had cut a building at half. Killer thinks that the other three are being ridiculous, with a laugh. Apoo attacks once more, but this time, Kid tells the others to cover their ears. Apoo clicks his tongue when he find out that his powers did nothing, thanks to Killer's quick thinking and the Massacre Soldier also points out that Apoo's powers only work when they can hear sounds, only to get a 'what' from the Luffy, Zoro, and his captain.
Meanwhile, the Beasts Pirates are exclaiming that there are a lot of Worst Generation members in Onigashima, and they should start taking their heads. Another adds that Killer has eaten a SMILE, hence turning him into a 'Pleasure'. Angered, Kid is told to stop picking a fight with the enemies by Luffy and the others.
As Who's Who remarks the Udon escapees, the higher ranking members of the Beasts Pirates talks about taking them all out but he retorts by saying that they should go searching for Kaido's son, Yamato, instead. He tells them that getting to Yamato is more important and they shouldn't let Sasaki beat him to it. Who's Who then goes on by finding out that Queen wanted to 'wipe somebody out' and says that he's not alone.
Big Mom is getting ready, wearing her kimono, and says that 'they' must be there soon enough.
Meanwhile, at the eastern side of Onigashima, Kin'emon leads the attack. The scabbards are also preparing to attack, but instead of going in all at once, they divide into two groups. The first half will breach the keep from the dome while waiting, and should they succeed, Kaido and Orochi will be within their reach. However, because of the outdated maps, the actual location looked different. Sanji spots a brothel and points out that they can sneak in through it without getting spotted. Inside the brothel is another member of the Tobiroppo, Black Maria, and Sanji is getting closer and closer to it. Nami says that they should go in too and Shinobu suggests that they should split up once more, as Kin'emon remembers that Momonosuke mentioned that he wanted to escape on his own. With this, Nami smiles and reassures him by saying that he should leave it to them while Carrot says that he should focus on the battle instead, while patting him. After Kin'emon thanks them for being supportive, someone is coming out of the brothel, and it is actually Sanji. He has a deflated expression, saying that the brothel is empty.
The attack proceeds. Kin'emon exclaims that once they spot something...but Big Mom, who is actually inside the brothel, notices the commotion outside and peeks. Kin'emon and the others has dove into the water, leaving her nothing to lay her eyes upon except for Chopper whom she shared eye contact with.
At the waterfall, Perospero commands to climb said body of water. The other members of the Big Mom Pirates asks what's Big Mom thinking - agreeing into an alliance - in which Smoothie replies that it's what she decided and she respects it. Daifuku echoes then tells them not to forget their main purpose; Mon'tdor and Galette says to take Monkey D Luffy's head, while Flampe goes on with her personal goal: to get Kaido to like her. They finally reached the top and reaches Wano, officially, when Perospero recalls they're in the same spot where King attacked them earlier. Another 'bird' is seen from the sky and they pointed out it's King, again, but it really isn't. Perospero shows a shocked expression upon recognising who that 'bird' is; it is Marco the Phoenix, in glasses, saying that he heard about the alliance between the Beasts Pirates and Big Mom Pirates. Troubled, the members of the latter panic as the former first divison commander of the Whitebeard Pirates come tipping their ship over.
Nekomamushi notices the ship tipping over then wonders what's going on. A sly grin from Izo is shown as he points out that it's been a while since Marco took a move.
- One of the Numbers, Hatcha, is fully shown.
- It is revealed that Apoo's attacks can only reach where the target can hear them.
- Orochi was the one who forced Killer to eat a SMILE fruit.
- Who's Who's team is shown. He orders them to investigate Yamato's whereabouts.
- Who's Who also wants to kill someone.
- Kin'emon's team arrives at a brothel belonging to Black Maria. At this point, the team splits up in two, with one advancing to the rear entrance of Kaido's castle as originally planned and the other infiltrating the brothel to search for Momonosuke.
- The Big Mom Pirates attempt to enter Wano again, but they are stopped by Marco, who arrives along with Nekomamushi and Izo.