A fun guide to the 10 Republicans who made the debate
Welcome to the first US presidential primary debate - the first round in the longest electoral game show in the world. Ten lucky Republican candidates have managed to squeeze in enough name-recognition to win a spot on stage.
Since politics in the US is a spectator sport, we've added some tips on how to play along at home.
Divide the candidates among your friends, and see who gets the highest score.
Now let's meet our contestants. Come on down...
Who is he? Billionaire, reality television star, golf and real estate mogul, rider of golden escalators. The Donald is the one man who really needs no introduction. He exists whether you acknowledge him or not. He's at the top of the polls in the Republican Party, and the establishment's attempts to strike him down have only made him more powerful than you can possibly imagine.
Expected strategy: Trump will be Trump. If he's attacked by one of the other candidates, expect him to hit back. Donald says he doesn't start fights, he finishes them. Maybe he'll say something crazy, and everyone will laugh. Maybe he'll stay serious, and everyone will be impressed with his gravitas. Either way, he comes out ahead.
Win a point if: He promises to "make America great again". He believes he's the man to do it, and he's got the hat to show it.
Win a million points if: He wears the hat on stage.
Lose a point if: He says "you're fired". That Apprentice catchphrase is so 2004.
Who is he? Former governor of Florida, son of one president and brother to another, the man with 99 problems but having enough campaign money isn't one. Bush started the year expected by many to emerge as the clear frontrunner, but that hasn't happened. Jeb! - as his logo exclaims - is just one of several upper-tier candidates getting lapped in the polls by Trump.
Expected strategy: Bush will likely try to be the grown-up in the room. If other candidates get mired in a slug-fest with Trump, he can try to stay above the fray and pitch himself as the mature, presidential alternative. It was a plan that worked (eventually) for Mitt Romney in 2012.
Win a point if: He vows to boost US growth from 2% to 4% as president. Call it the "seven-minute abs" campaign promise. Who wants two when you can have four?
Win a million points if: He says he agrees with his brother on anything. "George W Jeb" is getting hammered on his familial ties to the 43rd president, and proving he's "his own man" has been one of his most daunting tasks.
Lose a point if: He mentions his campaign "swag store", as he did in New Hampshire Monday night. There are a lot of words that can sound presidential. "Swag" isn't one of them.
Who is he? Governor of Wisconsin, Kohl's discount store shopper, bane of public employee unions everywhere. Walker made a big splash in an Iowa presidential forum back in January, and he's become a popular pick as a candidate who can appeal to both conservative activists and the Republican establishment.
Expected strategy: This will be a big test for Walker as a top-tier candidate. He's been criticised in the past for lacking presidential timbre, so his goal will be to look and act like a serious, informed politician, while avoiding any major gaffes.
Win a point if: He mentions Ronald Reagan. He got married on the late president's birthday and every year throws a Reagan-themed anniversary party. He's a big fan.
Win a million points if: He talks about his fitness tracker. He wears one all the time and credits it with keeping him in shape. You may not see it under the sleeve of his debate-night suit jacket, but trust us, it's there.
Lose a point if: He cites heading the Wisconsin National Guard in a foreign policy answer. Every time governors trot this line out they sound only slightly less ridiculous than when Sarah Palin mentioned how close Alaska is to Russia.
Who is he? Ordained minister, former Arkansas governor, former conservative radio and television talk host, model for awkward family photos. Huckabee was the surprise of the 2008 presidential race after winning the first-in-the-nation Iowa caucuses. Now he hopes to recapture that old campaign magic.
Expected strategy: Eight years ago Huckabee ran as a conservative with a heart. After years as a Fox talking head, he now seems to be running as a conservative who eats hearts. Expect lots of blanket condemnations of liberal orthodoxy, particularly when it comes to Barack Obama's foreign policy.
Win a point if: He doesn't make a reference to Nazi Germany. The candidate is a walking embodiment of Godwin's law.
Win a million points if: He bursts out into song. He and Democrat Martin O'Malley are the only presidential hopefuls who front rock bands.
Lose a point if: He makes a joke that bombs. He styles himself as a good-natured cut-up, but as the old saying goes: "Dying is easy. Comedy is hard."
Who is he? Florida senator, son of Cuban immigrants, former college football player, parched-mouth sufferer. Rubio is considered a rising star in Republican circles, but many were surprised that he decided to eschew a sure-thing second term in the US Senate for a presidential bid, particularly with Floridian Bush already in the race.
Expected strategy: Rubio became a popular pick as a campaign dark horse, but after an early bounce in the polls he's become mired in the crowded middle of the pack. He's the youngest candidate on the stage, so he'll have to project maturity and remind everyone of his potential.
Win a point if: He mentions the American Dream. His child-of-immigrants story is compelling and he isn't shy about recounting it, so you can probably go ahead and pencil this in the plus column.
Win a million points if: He gets caught on camera drinking water. For a long time Rubio's awkward attempt at hydration during a 2013 State of the Union response was all anyone knew about him.
Lose a point if: He talks about immigration. He supported Senate immigration reform in 2013 before it became radioactive among much of the conservative base. Any time he spends on the subject will remind Republicans of this.
Who is he? Paediatric neurosurgeon, best-selling author, child of urban poverty, separator of conjoined twins. Carson was in double digits in opinion polls for much of the year but has slipped of late. He has a loyal following that's helped him nab several conservative straw poll victories.
Expected strategy: This is the first time Carson has been in a political debate, so his goal is to prove he belongs there - which is a pretty low bar among this crowded field. He's the "other" non-politician on the stage and could seek to offer himself as a less abrasive, more thoughtful choice for disaffected Trump supporters.
Win a point if: He tells the story about the patient who mistook him for a hospital orderly.
Win a million points if: He compares Obamacare to slavery. It wouldn't be the first time, but he's toned down his bombastic rhetoric recently.
Lose a point if: He says progressive taxation is socialism. If it is, then the US has been a socialist state since 1913.
Who is he? Senator from Texas, former Supreme Court clerk, Canadian-American, aspiring Simpsons voice actor. Cruz beat a heavily favoured Republican in his 2012 Senate race and quickly made waves in Washington, spearheading multiple high-profile filibusters and government shut-downs
Expected strategy: Cruz is a former college debate national champion, so he enters Thursday night with rhetorical knives sharpened and high expectations. He's pitching his campaign to evangelical conservatives and grass-roots Tea Party true-believers, so expect him to spend plenty of time throwing them chunks of fresh red meat.
Win a point if: He attacks "the Washington cartel". Although it sounds like a minor-league soccer franchise, it's his term for the insiders and establishment politicians he's made life difficult for during his Senate tenure
Win a million points if: He attacks Donald Trump. While other candidates have been going after the top dog, Cruz has showered him with praise, perhaps hoping to pick up the pieces if the billionaire flames out.
Lose a point if: He talks about cooking bacon on the barrel of a machine gun. OK, he likes guns and he likes bacon. But his latest attempt at creating a viral video was just cringe-worthy.
Who is he? Senator from Kentucky, opthalmologist, son of former presidential candidate Ron Paul, libertarian (sort of), enemy of hairbrushes everywhere. Paul launched his campaign as the candidate who could combine the grass-roots support of his father's libertarian true believers with a more mainstream Republican appeal. So far, however, it seems he's alienated both groups.
Expected strategy: Paul will likely play up the anti-big government, surveillance-state positions that prompted Time magazine to once label him "the most interesting man in politics". Given how his campaign has struggled in the past few months, he could come out swinging at the other candidates. At this point, he has little left to lose.
Win a point if: He mentions the "Washington machine". Like Cruz's Washington cartel, Paul's machine is the windmill he tilts at.
Win a million points if: He's wearing cowboy boots. The Texan has a penchant for fancy footwear, but such a debate fashion statement may be a bit too unorthodox even for Paul.
Lose a point if: He has to talk about the Iran nuclear deal. It's the kind of foreign policy topic that will only hurt him, no matter how he answers it.
Who is he? Governor of New Jersey, former US attorney, bellicose YouTube star, Dallas Cowboys superfan. Christie could have presented a serious challenge to Romney in 2012, but he chose to sit out the race. He may have missed the presidential boat, as his popularity both in New Jersey and nationwide has precipitously dropped since then.
Expected strategy: Donald Trump has stolen Christie's "tell it like it is" mojo, so the debate may be his chance to win some of it back. Look for him to try to be blunt but not blustery, touting his ability to get things done in liberal-leaning New Jersey.
Win a point if: He talks about his late Sicilian mother. He cites her as his "moral compass" - the way he tries to soften his brash image.
Win a million points if: He mentions Bruce Springsteen. He used to be a huge follower, but the New Jersey musician very publicly skewered the governor in a January 2014 Tonight Show musical satire.
Lose a point if: Hurricane Sandy comes up. The only thing Republicans remember from the natural disaster is Christie's pre-2012 election embrace of Mr Obama - and they have never forgiven him for it.
Who is he? Ohio governor, former congressman, friend of U2's Bono, 2000 presidential candidate who was beaten by a guy named Bush. Kasich is a late entry into the Republican field, but his post-announcement bounce was enough to sneak him into the final spot on the debate stage.
Expected strategy: Kasich's goal will be to appeal to the moderate, establishment Republican crowd, which puts another Bush squarely in his cross-hairs. If he contrasts favourably with the Floridian, and he could become the choice as the anti-Trump.
Win a point if: He talks about finding God after his parents were killed by a drunk driver. It's Kasich at his most heartfelt.
Win a million points if: He leads the home-state Cleveland crowd in an O-H-I-O football chant.
Lose a point if: Someone mispronounces his last name. The ch in Kasich is a hard k.
Try again next time - Rick Perry, Rick Santorum, Carly Fiorina, Lindsey Graham, Bobby Jindal, George Pataki and Jim Gilmore