Now in its 25th season, Big Brother has had to come up with some twists and turns to help shake up the game. There are consistently new elements introduced to the series and exciting new competitions, or variations of old ones. But a handful of competitions, including endurance, Head of Household, Veto, and Have Not, have continued to come back because the fans can't get enough of them.

The competitions make up the backbone of the Big Brother series. Players gain power in the House and can get immunity from elimination by winning these games. The fans love seeing the compeitions play out and love to see someone who dominates the games. Even many of the players grew up watching the show and are excited to partake in one of the most iconic competitions. It's always a highlight of the episode when a classic competition begins.

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10 Knight Moves

Seasons 3, 6, 16, 22

Players standing on a massive chess board in the Knight Moves competition on Big Brother.

Knight moves isn’t exactly the most exciting competition to watch on the iconic 2000s reality show. Players as pawns walking across a massive, life-size chess board. What’s most intriguing about the competition is that there’s nowhere to hide. Players step on and turn over tiles, rendering them unusable.

This game really tends to reveal the alliances in the house as it becomes obvious who is going after each other. It was this competition that led returning player Enzo Palumbo to lash out at his housemates, believing them to be teaming up against him to prevent him from winning.

9 Slippery Slope

Seasons 8, 11, 13-21, 23-24

Players going back and forth on a slippery surface in the Slippery Slope competition on Big Brother.

Slippery Slope goes on for hours, often turning the episode into a two-part episode. It’s tedious and repetitive, but fans love seeing how each player handles the pressure and conditions. Players slides down a slippery lane grabbing tiny cups of water from a barrel on one side and pouring it into a container on the other until a tiny ping pong ball at the bottom of the container rises far enough to the top for them to grab it.

The competition has traditionally slapstick humor as contestants slip, slide, and fall over. Some, however, prove their speed skating skills and maintain balance, zooming back and forth in their lanes. Whoever can navigate this slippery slope can win a big advantage in the House, and may make themselves a threat.

8 Bowlerina

Seasons 15, 17, 19, 23, Celebrity Big Brother 1

Two Big Brother players in tights and tutus turning themselves around on an overhead apparatus.

Pure, unadulterated fun, in Bowlerina, player dress in brightly colored tights and tutus. They spin around while holding an overhead apparatus until a timer ends, then bowl a ball to hit pins on the other side. They repeat this again and again, naturally getting dizzier and dizzier and looking sillier and sillier as the competition continues.

A variation of the competition was featured in Big Brother Season 25. Players were seated in a chair that spun around after which they had to navigate a moving platform and throw a ball onto a large game board to score points.

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7 The Black Box

Seasons 18, 20, 21, Celebrity Big Brother 1

A woman crawling in the dark with a head lamp in a scene from the Black Box competition on Big Brother.

Players enter a dark space to search for items and place them in the right position. It usually involves crawling through tiny doorways, encountering sticky, gross sludge, and even being scared by bumps in the night. In more recent versions, players have been given a headlamp to help.

The latest variation featured in season 25 saw players sent into a haunted house where they were faced with creepy replica scenes from the movie The Exorcist: Believer. What’s most entertaining about this time-based competition is each player’s reactions. Some are terrified while others aren’t phased at all.

Seasons 11-13, 15-18, Celebrity Season

A board with tiles that spell Responsibilities, Shannon Elizabeth standing beside it smiling in a scene from Celebrity Big Brother.

An amped up version of Scrabble, the idea is to collect as many letters as possible to spell a word and ring in. The person with the longest word in the fastest time wins. Fans forever poked fun at multi-season player Jeff Schroeder (who ended up in one of the longest-lasting reality TV show relationships) when he proudly spelled the non-word “Tectronics” out of the wooden letters.

In the celebrity season, actor Shannon Elizabeth spelled the longest word ever for the challenge with “responsibilities.” Players must either take extra time in hopes of getting the letters they want or spelling something and ringing in quickly, hoping it’s the winning word. The game leads to hilarious outcomes every time.

5 BB Comics

Seasons 16-25

A woman wearing a green cape looking at a series of comic book covers in the BB Comics competition on Big Brother.

A competition that houseguests always look forward to playing, BB Comics features comic book character versions of past and current houseguests as superheroes, focusing on a particular part of their personality or something memorable about them in the house. The players zip line across a window that displays the comics, trying to recall every little detail, then find the comic book cover that perfectly matches it.

They do this again and again, ringing a buzzer whenever they think they have them all correct. As a timed competition, the pressure is on. Along with containing both physical and mental aspects, the competition is a fun one to watch as players are distracted at the hilarious depictions of themselves and their housemates.

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4 The Wall

Seasons 10, 12-25

Players holding on to a tilted wall in The Wall competition on Big Brother.

Appearing in various iterations through the seasons, The Wall competition has different themes each season but the same general premise: houseguests hold on to a wall for dear life, aiming to be the last one standing. What makes the competition fun to watch is that there are various things thrown at them through the duration, from intense winds to sludge/paint, and large objects. The wall also moves backwards and forwards while the fixtures to hold onto are small and the platform to stand on is thin.

The competition typically runs for hours, which means fans have to wait until the next episode to find out who won. Deals are usually made by the final two people in the grueling competition with one person agreeing to drop on purpose if promised safety. This is an intense competition that highlights both physical and mental threats in the game.

3 Pressure Cooker

Seasons 5, 6, 25

Players standing in a circle in a dark room, their hands on buzzers in the Pressure Cooker competition on Big Brother.

The Pressure Cooker endurance competition, whereby players are placed in a glass box and have to keep their hand on a buzzer the entire time, was featured in the early seasons, and it became one of the ones fans most asked to see return. Big Brother answered, finally bringing it back for the latest 25th season. Jennifer Vasquez famously won in season 6 after promising Kaysar Ridha she would keep him safe, only to vote him out immediately after. That competition was the longest ever in the show’s history lasting 13 hours and 53 minutes.

In the 25th season, which added the element of darkness to the equation, a deal was made again between the final two remaining, though the person who promised safety honored the deal. It was just shy of breaking the record, lasting 13 hours and 49 minutes. This can be a grueling experience for the players and a stressful experience for the audience.

2 Hide and Go Veto

Seasons 8, 12, 16-21

Houseguests walking through a ransacked house after the Hide and Go Veto competition on Big Brother.

This escape from reality competition wasn’t designed to be as funny as it became. The idea is that each competitor runs into the house and tries to hide a Veto card as quickly as they can and as well as they can. Once all are hidden, the houseguests must search the house to try and find ones. The person who hides theirs the best wins.

However, thanks to prankster player James Huling, the competition became about ransacking the house. Huling would intentionally make a massive mess while searching, emptying cereal boxes, overturning mattresses, throwing clothes about, and creating chaos. While houseguests aren’t eager to deal with the aftermath, fans have looked forward to a player doing the same every season since.

1 OTEV

Seasons 7-9, 11-25

Seven players wearing capes and cowboy hats kneel before an animatronic figure in the OTEV competition on Big Brother.

By far the most popular competition on Big Brother is OTEV. As “Veto” spelled backwards, it’s always a Veto competition and one everyone wishes they could play. Like a warped version of musical chairs, players kneel on a platform and are given a clue by an animatronic character that also spews insults at them. They then slide down a wet ramp and quickly search through various zones filled with obstacles (including grimy ones) to find a card with the player’s name who coincides with the answer. The last person to climb up a rope on the ramp with the right answer is eliminated, and it continues until only one person is left.

From the hurled insults to the messiness and the frantic pace of the competition, OTEV is one of the most fun to watch and presumably one of the most fun to play in as well. It has the players on edge and the audience laughing at the ridiculousness of the competition.