On Day 19, host Jeff Probst announced the merge and Dakal, Sele, and Yara became one tribe. Immediately afterwards, Jeff announced the first re-entry duel of the season where everybody that went to the Edge of Extinction (aside from Sandra Diaz-Twine who raised the sail upon entering the island) would compete to return to the game. Tyson Apostol won the challenge, re-entering the game as the twelfth member of the newly merged tribe. The rest of the inhabitants were sent back to the Edge of Extinction to await their second and final re-entry duel while serving as members of the jury for the time being.
The newly merged tribe, soon to be named Koru, went back to the old Sele camp to set up and enjoy the merge feast. During that time, Denise Stapley told everybody how she blindsided Sandra on Dakal, intimidating Sophie Clarke. Knowing that he was the only old-school player to make the merge, Tyson made an alliance with Ben Driebergen, Jeremy Collins, and Tony Vlachos to keep those they perceived to be huge threats around while targeting those they saw as less flashy players such as Michele Fitzgerald, Nick Wilson, and Wendell Holland. However, this conflicted Jeremy as he already made a friendship with Wendell.
In the first individual Immunity Challenge, Denise and Jeremy were able to hold out the longest and each won immunity along with a Fire Token. Jeremy tried to push for Nick to go first as he was a social threat, but Sophie wanted to vote Wendell out instead to weaken Jeremy's grip. Sensing the change in dynamics, Jeremy tried to convince everybody to vote Adam Klein out instead as an easy agreement, making the latter paranoid. But come Tribal Council, Jeremy reluctantly went with the majority and Wendell was voted out 9-3. Wendell bequeathed his Fire Tokens to both Michele and Nick.
At the Reward Challenge the next day, the team of Ben, Michele, Sophie, Kim Spradlin-Wolfe, and Sarah Lacina won a Chinese takeout feast back at camp. However, Sarah decided to step down and give Nick her reward as it was his birthday the previous day, and out of apologies for the previous night's vote. However, that decision was questioned by everyone else as they saw it as a strategic move. Later that day, Michele found that she was being sold a 50/50 Coin from the Edge of Extinction that could be used up until the final seven, and bought it with her four Fire Tokens. After Kim won the next Immunity Challenge, the majority alliance talked about splitting the votes between Adam and Michele, but Ben convinced them to split the vote between Michele and Nick instead. Adam tried to rally numbers to vote out Sarah, but when Kim found out, she told Sarah, infuriating the latter. This caused Sarah to talk with Tyson about voting Adam out as she saw that he had the ability to sway people over, while the feud between Adam and Ben continued. Their argument did not stop come Tribal Council, and it led to multiple groups whispering about changes in plans. Before the votes were read, Adam made a last-ditch effort by trying to remove a fleur-de-lis decoration off the voting podium as he thought that it was a Hidden Immunity Idol. However, it was not, and Adam was voted out 8-2-1. He would bequeath his Fire Token to Denise.
On Day 24, the final ten were surprised by a visit from their loved ones. Jeff announced that instead of having a Reward Challenge, everybody could bring back their loved ones back to camp for the day. The following day, Tony won the next Immunity Challenge and began pressing the idea of voting Jeremy out due to his strategic gameplay, while Jeremy wanted to vote Sarah out. Two different alliances were formed during the day: one alliance consisted of Ben, Nick, Sarah, Sophie, and Tony, while the other alliance consisted of Denise, Jeremy, Kim, Michele, and Tyson. Each wanted to take out a threat from the other, spilling over into Tribal Council. This made Jeremy paranoid, and he used his Safety Without Power Advantage to leave Tribal Council, foiling Tony's alliances plans. Then, Sarah, after much convincing from Sophie, used her Vote Steal advantage to take Denise's vote, giving herself two for the night, and giving her alliance control of enough votes to split their votes. Although Kim played her idol on Denise, it was all for naught as the other side voted Tyson out 5-2-0, sending him back to the Edge. Since Tyson had no Fire Tokens on him, he did not bequeath any before heading back.
Early the next day, Tony found a Hidden Immunity Idol and decided to go back to the chaotic gameplay he employed in Cagayan. Tony pled loyalty to the minority alliance, but was met with skepticism from Denise and Kim. On Day 28, Tony received an Extortion Advantage the Edge of Extinction, which required him to pay six Fire Tokens or lose his spot in the next Immunity Challenge and his vote at the next Tribal Council. Since Tony only had three Fire Tokens, he was able to get a Fire Token each from Ben, Jeremy, and Nick, having enough to pay the ransom. He would go on to win the Immunity Challenge, and back at camp, the majority alliance agreed to split the votes between Jeremy and Michele on the chance that either them had an idol. Meanwhile, Denise and Kim decided to betray Jeremy and join the majority alliance. Unbeknownst to anybody, Tony secretly approached Jeremy, Michele, and Nick about blindsiding Sophie, believing that she was getting too close with Sarah. Although Jeremy was hesitant to the idea, he and Michele joined Nick and Tony, and Sophie was blindsided 4-3-2, flushing her unused idol in the process. Sophie would split her two Fire Tokens between Kim and Sarah.
Once the tribe returned to camp, a livid Sarah confronted Tony on his betrayal. Come the next day, Tony continued his old style of gameplay by creating a "spy nest" near the water well, with only Sarah knowing about it. Meanwhile, Kim started to realize the power that Tony had over everybody and tried to raise numbers around her to get him voted out. At the same time, Ben found Sophie's re-hidden idol, with only Tony knowing about it. At the Immunity Challenge, both Denise and Tony were able to outlast everybody else and won immunity, foiling Kim's plans. While Jeremy became the target once again, Tony found out Kim's original plan from Ben, and tried to rally his allies to vote her out. Meanwhile, Michele gave Jeremy her 50/50 Coin so that he would have some protection, but he did not like the idea of leaving his fate to chance. At Tribal Council, Jeremy did not play the 50/50 Coin, while Sarah declined Tony's offer to take his idol. None of this mattered though as Kim was voted out 5-3, and she split her three Fire Tokens between Denise, Michele, and Sarah.
Back at camp, Jeremy returned the 50/50 Coin to Michele. While Sarah and Tony wanted Nick gone over Jeremy next, the plan was foiled when Nick won the following Immunity Challenge. With Nick immune, the majority agreed to vote out Jeremy, although Sarah and Tony expressed reluctance. Since everybody knew about Michele's 50/50 Coin, they decided to split the votes between her and Jeremy in case she played it. Come Tribal Council, Michele played the 50/50 Coin, which landed on "Safe", but this did not matter as Jeremy was voted out 3-2-0. Jeremy bequeathed his two Fire Tokens to Michele.
Now alone, Michele tried to shake things up by telling Sarah that Tony would win in the end, but was rebuffed. Meanwhile, Nick found out that he was being sold a challenge disadvantage from the Edge of Extinction, allowing him to anonymously play it on somebody in the next Immunity Challenge and give them a disadvantage for eight Fire Tokens. Since Nick only had six Fire Tokens, he asked Michele to help him out, and she gave him her two Fire Tokens, allowing him to pay for it. Nick played it on Ben, forcing the latter to fill up 30% more of his beam in the Immunity Challenge in the process. Michele ultimately won immunity, foiling the majority alliance's plans. While Michele and Nick wanted Denise out, Ben and Denise wanted Nick out instead. Denise bought a big of rice for the tribe with her Fire Tokens, reasoning that she would want to go to the Edge of Extinction with a full belly if she were voted out that night. However, this was just a ploy by the majority to get Michele and Nick to believe that Denise was the next target. Despite Tony overhearing Denise talking with Ben and Sarah about a Final Three without him, he joined the majority in voting Nick out 4-2.
On Day 35, the second Edge of Extinction re-entry duel occurred and was won by Natalie Anderson, allowing her to re-enter the game. Returning back to camp for the first time since her elimination, Natalie aligned with Michele and showing her the Hidden Immunity Idol that she bought while on the Edge of Extinction. In addition, she told everybody that the jury felt that Tony was the best player of the final five and would vote for him to win if he made it to the Final Three. This unnerved Sarah as she had been working with Tony the entire game, and felt that she would be overlooked by the jury due to being a woman. On the other hand, Tony was frightened by Natalie's presence as he recalled how Chris Underwood won Edge of Extinction won after spending most of his time on the Edge of Extinction.
At the following day's Immunity Challenge, Michele came from behind to win immunity. Tony feared that Natalie had an idol and tried to push his alliance to split the votes between Denise and Natalie. However, Ben did not want to do it as he refused to see Denise as an expendable number, and Sarah felt that Tony was being paranoid. However, come Tribal Council, Tony's fears were realized as Natalie played her idol for herself. This resulted in both Ben and Tony playing their idols for themselves, and when the votes were read, Natalie's four votes were voided, and Ben's two votes were also voided. Because of the resulting null vote, Jeff said that the only two people that the four immune castaways could vote for were Denise and Sarah, and per the rules of Survivor, a tie would force the two women in a fire-making challenge as the tiebreaker. In the end, the four unanimously voted Denise out.
Back at camp, Tony lamented having both his and Ben's idols be played as they had no more protection, and went searching for a new one when everybody else went to bed. However, Tony came up short and at the crack of dawn, everybody else got up looking for the idol, which was claimed by Natalie. At the Immunity Challenge, Tony and Ben were neck-and-neck, but the former managed to claim victory first. Natalie pulled Sarah aside to the water well and tried to convince her to vote Ben out and keep the women together, showing Sarah her idol in the process. Unbeknownst to Natalie, Sarah had brought her there so that Tony could overhear everything up in his spy nest, and Sarah and Tony planned to vote Michele out since Natalie had an idol. However, Ben talked with Sarah about voting him out instead, feeling that he had no chance of winning the game himself and hoping that it would be good for her resume in the Final Three. After thinking it through, Sarah joined the women in voting Ben out 3-2, taking Tony aback.
On Day 38, Natalie won the Final Immunity Challenge, securing her spot in the Final Three. As she left camp to think over her choices, Michele, Sarah, and Tony began practicing their fire-making skills in case they were forced to compete in the fire-making challenge. Although Natalie considered putting herself up against Tony, she decided to bring Michele with her to the Final Three, pitting Sarah and Tony, the Cops-R-Us duo, against each other in the fire-making challenge. In a close race, after Sarah's initial fire died out, Tony had the lead and burned through his rope first. Tony claimed the final spot in the Final Three, while Sarah was eliminated and became the final member of the jury.
On Day 39, the Final Three had the traditional breakfast feast before heading to their Final Tribal Council. During their pleas, Natalie commented how, despite living on the Edge of Extinction since Day 2, she was still an influential player by finding and selling advantages from the island, and how she played hard after coming back. Tony, meanwhile, claimed that he created bonds with people and kept a dominant game throughout his time. Finally, Michele pointed out how she was in the bottom since the beginning, but despite being left out of multiple votes, still fought hard to make it to the Final Three. Months later, Jeff spoke with the Final Three through livestream, and after tallying the votes, it was revealed that Tony won the title of Sole Survivor in a 12-4-0 vote, officially making him the second two-time winner in Survivor history.
- Despite Koru's buff color being black, all the chyrons in its members' confessionals were in gold.
- Koru is the first merged tribe on an all-returning player season to have a male majority.