O-Black Water

O-Black Water (also known as Polar Express) is a recurring team challenge in Survivor. It first appeared in and reappeared in .
==Rules==
The castaways are divided into two teams of five. One at a time, each castaway will cross three obstacles: a ramp, a net obstacle, and a balance beam. Once all five members have completed the course, they will dive into the water for a grappling hook, which they will use to secure five rings. The first team to grab all their rings wins.
The international version of this challenge uses the same water obstacle course, but replaces the grappling hook element with a puzzle element.
==History==
=== United States ===
In , the teams were neck and neck at the grappling portion, but the blue team of Dan, Mike, Shirin, Sierra, and Tyler pulled ahead, winning a feast of chocolate as their reward.
In , the blue team of Andrea, Aubrey, Brad, Debbie, and Sierra had a huge lead and won a picnic reward after Cirie on the orange team was unable to cross the balance beam. After the challenge was over, Jeff Probst and Cirie's castmates all encouraged her to cross the balance beam, which she did, earning a round of applause from everybody. It was also at this challenge that Sarah Lacina found a secret advantage at the sit-out bench after the challenge concluded.
=== Australia ===
In , the challenge was used as a tribal Immunity Challenge. The castaways had to dive off a tower, go up and down a slide, and cross a net obstacle. Once on shore, one member will use a machete to hack through a pole, releasing a bag of puzzle pieces that two tribe members will use to piece together a seashell. Asaga member Henry Nicholson succeeded in his plot to throw the challenge, granting Samatau victory and sending Asaga to Tribal Council.
===South Africa===
In , the challenge appeared as the first tribal Immunity Challenge. The three tribes had to start by taking apart a and carrying the pieces across the water obstacle course. They would then reassemble the block puzzle, with the first two tribes to do so winning immunity. The puzzle proved to be a challenge for all three tribes as they spent nearly 90 minutes in the rain struggling to reassemble their blocks. In the end, Ta'alo finished their puzzle first, while Laumei scored a second-place finish to send Sa'ula to Tribal Council.
==Winners==
<tabber>United States=
Episode	Challenge Type	Winners
 	Team Reward 	
 	Team Reward 	
|-|Australia=
Episode 	Challenge Type 	Winners
Episode 6	Tribal Immunity	
|-|South Africa=
Episode	Challenge Type 	Winners
 	Tribal Immunity	
 	Tribal Immunity	
</tabber>
==Gallery==
<tabber>United States=
S30 press images ep9 0018.jpg|Will crossing the balance beam in .
S30 press images ep9 0017.jpg|Carolyn sliding in Worlds Apart.
S30 press images ep9 0016.jpg|Mike makes a dive. (Worlds Apart)
S34_Ep10_SG_031.jpg|Tai competing in .
S34_Ep10_SG_033.jpg|Brad and Tai competing in Game Changers.
S34_Ep10_SG_036.jpg|Sierra crossing the balance beam. (Game Changers)
|-|Australia=
AU2017-Ep6-ImmunityChallenge.jpg|The challenge in .
AU2017-Ep6-SamatauImmunity.jpg|Tessa working on the puzzle for Samatau in 2017.
AU2017-Ep6-AsagaImmunity2.jpg|Sarah works on the puzzle, while Henry tries to throw it. (2017)
</tabber>
==Trivia==
* Sierra Dawn Thomas is the only person to compete in this challenge twice. She won both times she competed.
* Both times the challenge was used in the United States, the Blue Team won. Both times the challenge appeared internationally, the teal tribe lost.
==References==
Category:Survivor (U.S.)
Category:ChallengesCategory:Recurring Challenges
Category:Survivor: Worlds Apart
Category:Survivor: Game Changers
Category:Worlds Apart Challenges
Category:Game Changers Challenges
Category:Australian Survivor (2017)
Category:Australian Survivor (2017) Challenges
Category:Survivor South Africa: Island of Secrets
Category:Island of Secrets Challenges