Reality competition series Big Brother, which casts up to 16 people and puts them into a house to live together through the summer, cut off from the real world, is characterized by scheming, forging alliances, and competitions.

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There are two main types of competitions: one for Head of Household (HoH), which happens each week, and one for Power of Veto (POV) that follows. The person deemed HoH gets to nominate two people for eviction. The POV, meanwhile, gives the winner the opportunity to remove one of those people – themselves included – from the eviction block, forcing the HoH to put someone else up in their place.

While sometimes, players choose not to use the Veto, other times, it has been used in a way that totally shakes up the game.

Cody Puts Up Paul

A shirtless Cody Nickson looking angry in Big Brother

This was one of the best veto plays and a bold move on a season where people weren't afraid to make them (hint, hint, All-Stars!) But it completely backfired on Cody. There was a Temptation Twist Cody didn't know about.

This allowed two-time player Paul to nullify Cody's choice, forcing him to nominate a fourth person. Pretty early on in the game, nominating four people doesn't exactly put you in a great position. Cody made too many enemies off the bat, killing his game. But it did make for juicy television.

Dan Manipulates Ollie

Big Brother Ollie

Remember that time when Dan shed tears during an HoH competition, pleading with Ollie to let him win so he could see a picture of his girlfriend? He negotiated a deal that would let Ollie pick one of the nominees as well as the veto replacement, should there be one.

Of course, Dan went back on this deal when it came time to name names and put up Michelle instead of Keesha, who Ollie wanted him to get nominated. Some might say this was a bad play, but Dan held all the cards and, in the end, it worked out since he won the game.

Kaysar Getting Backdoored

Kaysar from Big Brother, walking back into the house with his bag over his shoulder.

Kaysar was one of the most beloved players, a fan favorite who returned to play in the second All-Stars season. In his original season, he gave up an HoH win to Jennifer, who he believed made a rock-solid deal with him to keep him safe in exchange for him throwing the competition.

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Except when his ally Janelle managed to win the Power of Veto and take herself off the block, Jennifer did a complete 180 and put up Kaysar, ultimately leading to his eviction. It was a dirty game move but a great Veto play that no one, particularly Kaysar, saw coming.

Danielle Saves Dan

Big Brother Danielle

In one of the most manipulative moves in the show's history, Dan used his loyal ally Danielle and convinced her to take him off the block. He promised he wouldn't evict her ally, Shane. But once he was off and became the only vote to evict, he did exactly that.

Danielle's shocked face, mouth agape, at the declaration, has become a thing of memes. But even better than that was when Dan was able to further manipulate the situation to make it look like he and Danielle were at odds, then tell her it was all an act and he did it in her best interests, making her actually believe and forgive him!

Nakomis' Invention Of The Blindside

Nakomis from Big Brother, sitting and smiling.

To fans of Big Brother, especially those who have only watched recent seasons, the concept of the "blindside" or "backdoor" seems like it was always part of the show. But it didn't always exist. Someone had to have come up with the idea.

That someone was Nakomis in season five who, together with Marvin, contrived a plan to put two people up, use the veto at the 11th hour to remove one of them, and put up the person who was their real target. In that case, it was Jase, who became the first victim of the Big Brother "blindside/backdoor" plan.

Maven Goes Down

Big Brother Matt Raven

By the time Raven and Matt, arguably the most annoying showmance couple in the show's history, were put on the block together, viewers were tired of their nonsense and happy to see one of them go. And apparently, so were their housemates.

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While the supposed plan the whole time was to use them as pawns when the real target was Kevin, Jason through them for a loop when he announced after winning veto that he was keeping the nomination the same.

Evel Dick Saves Himself

Dani Briones and Evel Dick Big Brother

Evel Dick went on to win Big Brother 8, but it wasn't an easy ride for the self-proclaimed villain of the season. He ruffled feathers, said what he wanted to, and made no secret of his alliances. So, it's no surprise that he and his estranged daughter Dani, who is currently playing for her third time in All-Stars, were put on the block together.

While it seemed a certainty that one of them would go home, Evel Dick pulled out a veto win and, not surprisingly, took himself off the block. Stupidly, Dustin volunteered to be nominated thinking he would just be a pawn warming a seat. Instead, he was sent packing. The reason? Eric Stein was named America's Player and had to fulfill viewers' wishes, even when they weren't his own.

The Coup D'etat

Jeff from Big Brother 11

This wasn't technically a veto play but it's worth including because the power was so plentiful that Jeff didn't even need to win a veto in order to use it. Instead, he was simply able to stand up and declare that he was taking over the HoH that week, removing the two people they nominated and putting up his own two picks.

In the end, Jessie Godderz went home in a huge blindside and Chima Simone went off the rails, angry that her HoH was deemed effectively useless. She ended up getting ejected from the game for her rule-breaking actions that included taking off her mic pack and throwing it into the pool.

Frankie Takes Himself Off The Block

Frankie holding two ropes during a two-person competition on Big Brother, looking panicked.

Frankie kept his true identity as the older brother of mega pop star Ariana Grande a secret for much of his time in the house. But once this lie was revealed, and houseguests began to question his loyalty, they totally turned against him.

His own alliance even abandoned him in a veto competition, happy to take a loss so he would go on the block. Except he still won a two-man competition even though he was playing by himself against two others, and removed himself from the block. It was one of the most intense moments of the season, and arguably of the series.

Dan's Funeral

Dan Gheesling addressing the houseguests during his famous Funeral speech on Big Brother.

One of the most iconic moments in the series, after being nominated, Dan spent 24 hours in solitary confinement as an unrelated punishment. During that time, he concocted a master plan to hold his own funeral. Appearing all in black, he proceeded to gather everyone together and doll out compliments to all but Danielle, whom he pretended to have had a falling out with in order to convince the others to keep him in the house.

It worked and Jenn followed through with a new plan to put up Britney in his place.

NEXT: Big Brother 22 All-Stars: 10 Ways It's The Worst Season (So Far)