A Fazenda 8

A Fazenda 8 (in English: The Farm 8) is the eighth season of the Brazilian reality television series A Fazenda, which premiered September 23, 2015, on the Record television network. This season is part of a millionaire contract signed in 2011 between Strix Television and Rede Record which guaranteed the show's rights until 2019.

This season marks the debut of Roberto Justus hosting the show, replacing Britto Junior, who hosted the previous seven seasons. Gianne Albertoni returns as the show's social media correspondent on A Fazenda Online and events of sponsorship and bonuses are hosted by Bruna Calmon. The grand prize for the winner is R$2 million without tax allowances, with a brand new car offered to the runner-up.

The teams Rabbit, Sheep and Ostrich (present on the seasons 3, 4, 6 and 7) became extinct and were replaced by two teams (Axe and Saw).

In this new season, the barn was replaced by the stall. Every week, three contestants will have to share space with the horses and sleep beside the animals.

Below is biographical information according to the Record official site, plus footnoted additions.
(ages stated are correct at the start of the contest)

Since season 5, contestants compete to win the Key Power each week. The Key Power holder is the only contestant who can open the mystery box located at the Farm. However, opening the box will unleash either a good consequence or a bad consequence at the nomination process.

This season, only two pre-selected contestants (one from each team) are allowed to compete each round. The winner becomes the Key Power holder for the week, while the loser is sent to the stall, along with two other contestants (one from each team) selected by the winner of the round. The Key Holder's choice is marked in bold.

The Instant Choice continued on this season. During the designated/announced five-minute voting window, Twitter users (with public accounts only) may vote to select a contestant to receive a special opportunity not available to others (which may or may not influence directly in the game) by tweeting the option's keyword along with the show's designated hashtag.

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Wikipedia