In many seasons, the tribes have been switched before the merge. The members of each tribe are swapped around. Sometimes the tribes are switched by doing a random shuffle to a schoolyard pick, where two players ("captains") would start picking players for their tribe. There has also been a Tribe Switch which is done by allowing players to join the other tribe. This process usually defeats many early alliances and strategies, and can cost a player the game early, or save them from being voted off early.
When there are 8 to 12 players left in the game, the two tribes merge. When they merge, the two tribes come together to make one new tribe. From this point, Challenges are won by one person. The merged tribe also chooses a new tribe name and makes a new tribe flag with materials given by production. There was no merge in "". The Koror tribe had won every immunity challenge, and members of the other tribe, Ulong, were being voted off one by one. When there was one Ulong member left, they simply joined Koror.
In the later seasons, hidden immunity idols have been made available. These idols, usually a small object that fits with the theme of the "Survivor" location, are hidden near camp or on Exile Island, with clues on its location given, usually to a chosen player (in "Guatemala") or to exiled or kidnapped players. Once found, the player with an idol may keep it or give it to another player before the start of Tribal Council, and it may not be stolen from that player. The player doesn't have to show this idol to other players, though may use it to join alliances and for voting purposes. Other players may find out that someone has the idol by peeking into other player's personal items. In the first few seasons of the twist, only one idol was ever in play, but in "Survivor: Fiji", "Survivor: China", "Survivor: Tocantins" and "Survivor: Samoa", two hidden immunity idols were made available to the players (one at each camp). The hidden immunity idol can only be used up until and including the Tribal Council of the final four or five players, depending on the season.
The use of the idol by a player to become immune has changed through the seasons:
During "Guatemala", the hidden immunity idol was not returned to the game after its use. Since then, if the idol is played, or the player with the idol leaves the game without playing it, the idol is replaced at a new spot to be found, and new clues are given out. During "Gabon", the players all decided to throw a hidden immunity idol into the sea. In this case it was not replaced at a new spot. In some seasons, fake hidden immunity idols have been made by contestants; these idols don't work if played.
The idea of Exile Island was started in "", when a player had to stay alone on a beach due to losing the Immunity Challenge. The idea was later used again in "" and was used in every season after that, except "" and "". A chosen player is sent ("exiled") to a small island away from the main tribe camps, usually for at least a day after a reward challenge and returning at the next immunity challenge. The player chosen may be the first loser of a challenge (as was the case in ""), or a person chosen by either the winning or losing tribe while the players are divided in tribes, or an individual challenge winner in the individual phase, after the merge. In "Micronesia" and "Tocantins", one person from each tribe was sent to Exile Island. Unless stated otherwise, players who win the right to choose who goes to Exile Island may also choose to go themselves.
Also, whenever the number of players is uneven when tribes are being made (in division or switching, but not merging), the player without a tribe will be "tribeless" and sent to Exile Island after formation ("", "", and ""). In this case, the player will return and join the tribe which loses a member at the next Tribal Council.
Once chosen, the exiled player is taken to the island by boat (or given a map to the "island"). On the island, there are few tools to survive with, usually a water canteen, a machete, a pot, and a small amount of shelter. The little amount of food on Exile Island can make a player weaker, causing them to perform worse in challenges. The separation from other players can cause a player to become on outcast on their tribe. Players are often sent to Exile Island for one or both of these strategic reasons.
The person exiled gets a clue to the hidden immunity idol, which may or may not be located on the island, an "instant comfort" (as in ""), or (as in "") the right to change tribes. If the exiled player is asked to return after the Tribal Council (whether they belong to a tribe or not), they will also be safe from being voted out at that Tribal Council.
Tribal Council is held at the end of each episode. Here, the tribe votes one person out of the tribe. The first time any player visits Tribal Council, they are asked to take a torch and light it from a fire pit. They say that "this is part of the ritual of Tribal Council because fire represents life. As long as you have fire, you are still in this game. When your fire's gone, so are you". If the Jury has already been started, they are asked to enter and watch. Probst then asks the players questions about details and events since the tribe's last Tribal Council. Before the vote, if a player has been awarded individual immunity through an immunity challenge, he is then asked if he wants to give it to another player. Whoever has the immunity after this possible switch cannot be voted out.
The players then vote for another player in secret, and the player who gets the most votes must leave the game. Players cannot vote for themselves. Players also have to write neatly, and avoid using of uncommon nicknames. If the number of votes for one player is above half of the total votes, Probst will stop reading, and that player is eliminated, keeping the rest of the votes in secret to the players themselves.
As said earlier, the player(s) with the Hidden Immunity Idol(s) get the chance to play the idol at certain points at Tribal Council.
The eliminated player's fire is put out, and Probst tells them "The tribe has spoken" and "It's time for you to go." The player then leaves the Tribal Council area and says some last words that are shown at the end of the episode. The rest of the tribe members are then told to return to camp with their torches; in some seasons, this has allowed a tribe access to a source of fire, while in other seasons, the tribe is not allowed to return to camp with their torches lit if they do not yet have their own source of fire or a way of starting one.
When there is a tie (where two or more players have the same number of votes) before there are four players left, the non-tied players will vote once again, where the only possibilities for elimination are the tied players. If the second vote does not break the tie, a two minute discussion will start where the non-tied players must come to a decision as to who should be voted off. If a decision is not reached in two minutes, the tied players are safe from being voted off and the non-tied players (except anyone who has won individual immunity) choose rocks out of a bag without looking. The player who chooses the differently colored rock is eliminated.
In the event of a tie at the final four, there will be a revote (However in "Survivor: Gabon", there was no revote in the final four and it went straight to the fire-making tie breaker challenge), but if the revote does not break the tie, the tied players will compete in a challenge. In "Palau", "Panama", "Cook Islands" and "Gabon", this challenge was a fire-making contest. In "Marquesas", the random rock tiebreaker was used at the final four, which host Jeff Probst later said was a mistake.