A majority of the team was built through the 2017 NHL Expansion Draft, and almost every player on the roster has improved their level of play from a season ago.
Here's a look at how the players fared before becoming Golden Knights and how they have done since joining Vegas:
Before: Had eight points (four goals, four assists) in 82 games as a bottom-six forward with the Philadelphia Flyers last season.
After: Bellemare had an NHL career-high 16 points and 10 assists, and tied his career high with six goals.
Before: Carpenter had two goals in 28 games from 2015-18 with the Sharks, including one assist in 16 games with them this season.
After: Claimed off waivers Dec. 13, Carpenter had 14 points, including nine goals, in 36 games with Vegas. He has three assists in the playoffs.
Before: In 60 games with the Dallas Stars last season, Eakin had 12 points (three goals, nine assists) including a career-low 3.7 shooting percentage.
After: Eakin had 27 points (11 goals, 16 assists) including two game-winning goals and a shooting percentage of 10.3 in 80 games. He has three goals and an assist in the playoffs.
Video: SJS@VGK, Gm1: Eakin redirects McNabb's shot home
Before: With the Minnesota Wild, Haula had 26 points (15 goals, 11 assists) in 72 games last season.
After: Haula more than doubled his point total (55) and almost doubled his goal total (29) in 76 games. He has six points (three goals, three assists) in the playoffs.
Before: Karlsson had six goals in 81 games with the Columbus Blue Jackets last season and 18 goals in 183 NHL games. He never scored more than nine goals in a season (2015-16).
After: Perhaps the biggest surprise of the NHL season, the top-line center finished with 43 goals (third in the League) and 78 points, both NHL career highs, including six game-winners. He also led the League in plus-minus (plus-49). His play has carried over into the playoffs; he has 10 points (four goals, six assists), including two game-winners, one in overtime.
Video: VGK@SJS, Gm3: Karlsson wins it in OT for Vegas
Before: Had 20 points (eight goals, 12 assists) in 65 games with the New York Rangers last season.
After: One of the few players on the Golden Knights who hasn't had a better offensive season, Lindberg had 11 points but scored more goals (nine) than he did last season.
Before: The center had an NHL career-high 30 goals last season and 51 points, but was minus-21 with the Florida Panthers
After: Marchessault had career bests in points (75), assists (48) and plus-minus (plus-36), which ranked second in the NHL behind Karlsson. He improved his point total by 24 and is tied for the team lead in playoff scoring with 11 (four goals, seven assists).
Video: VGK@SJS, Gm6: Marchessault cashes in on turnover
Before: Neal had 41 points (23 goals, 18 assists) in 70 games with the Nashville Predators last season and nine points (six goals, three assists) to help them advance to the Stanley Cup Final.
After: Neal had 25 goals, including six in the first four games of the season and the first three game-winners, and 19 assists for 44 points in 71 games. He has seven points (three goals, four assists) in the playoffs.
Video: SJS@VGK, Gm5: Neal capitalizes on lucky bounce
Before: Appeared in 11 games last season with the Detroit Red Wings and had one goal. Had 41 points (15 goals, 26 assists) in 51 games with Grand Rapids of the AHL.
After: Had 15 points (seven goals, eight assists) in 67 games with the Golden Knights this season.
Before: Had 46 points (18 goals, 28 assists) in 82 games with the St. Louis Blues last season.
After: Improved his point total by 20 with NHL career highs in assists (50) and points (66). Perron has seven assists in the playoffs.
Before: Had eight points (four goals, four assists) in 58 games with the Pittsburgh Penguins before he was traded Feb. 23.
After: Reaves has two assists in 21 games and has provided Vegas with a physical edge with 75 hits, more than three per game.
Before: With the Panthers in 2016-17, he had 37 points (15 goals, 22 assists) and was minus-13 in 80 games.
After: Smith, who is tied for the team scoring lead in the playoffs with 11 (one goal, 10 assists), had an NHL career-high 60 points (22 goals, 38 assists) and was plus-31 in 67 games this season.
Before: Tuch had no points in six games with the Wild last season, spending most of the year with Iowa of the AHL, where he had 37 points (18 goals, 19 assists) in 57 games.
After: In 78 games, Tuch had 37 points (15 goals, 22 assists), including 10 power-play points. He has seven points (four goals, three assists) in the playoffs.
Video: SJS@VGK, Gm5: Tuch knocks in rebound for PPG
Before: Played in 81 games for the Calgary Flames and had 16 points (four goals, 12 assists) and was a physical presence with 85 penalty minutes, second on the team.
After: Nominated for the King Clancy Trophy, awarded for leadership qualities and commitment to the community, Engelland, a Las Vegas native, had NHL career highs in assists (18) and points (23).
Before: Appeared in 49 games with the Los Angeles Kings and had four points (two goals, two assists).
After: A first-pair defenseman, McNabb had 15 points, including an NHL career-high five goals, in 76 games this season.
Video: VGK@LAK, Gm4: McNabb pots slick dish from Smith
Before: Had 13 points (six goals, seven assists) in 61 games with the Boston Bruins and missed two playoff games because of a knee injury.
After: Playing on the third pair, Miller did not miss a game during the regular season and had NHL career highs in goals (10), assists (31) and points (41).
Video: VGK@SJS, Gm3: Neal sets up Miller for PPG
Before: Sbisa played in all 82 games with the Vancouver Canucks last season and had 13 points and was minus-1
After: Despite missing 52 games because of injuries, Sbisa had more points (14) than he did last season and was plus-8 during the regular season.
Before: Had trouble cracking the Washington Capitals lineup at times and averaged 15:29 of ice time in 60 games.
After: Anchors the top pair and had NHL career highs in goals (five), assists (31) and points (36) and was plus-19 averaging a team-high 22:14 of ice time. Schmidt has five points (two goals, three assists) in the playoffs.
Before: Had nine points (two goals, seven assists) in 34 games with the Anaheim Ducks last season and 20 points (five goals, 15 assists) in 26 games with their American Hockey League affiliate in San Diego.
After: Theodore has found a home in Vegas, with an NHL career-high 29 points (six goals, 23 assists), including nine on the power play. He has five points (two goals, three assists) in the postseason.
Video: SJS@VGK, Gm1: Theodore finishes sweet passing play
Before: Finished the 2016-17 season as the backup to Matt Murray for the Pittsburgh Penguins, who won the Stanley Cup for the second straight season. Was 18-10-7 with a 3.02 goals-against average (the third-highest of his NHL career) in 38 games (34 starts).
After: Fleury was 29-13-4 with NHL career-bests in GAA (2.24) and save percentage (.927). He had four shutouts in 46 regular season games. In the playoffs, he is 8-2 with a 1.53 GAA, .951 save percentage and four shutouts, one fewer than the NHL record through two rounds of the Stanley Cup Playoffs.
Video: VGK@SJS, Gm6: Fleury makes 28 saves in Game 6 shutout
Before: Was 0-1-0 with a .5.88 GAA and .813 save percentage with the Boston Bruins last season and 11-14-5-1 with a 2.41 GAA in 32 games with their AHL affiliate in Providence.
After: Claimed off waivers on Oct. 3, Subban stepped in when Fleury was injured in October. He finished 13-4-2 with a 2.68 GAA and .910 save percentage in 22 games (19 starts) this season.
Before: McPhee, who was GM of the Capitals from 1997-2014, made one appearance in a conference final (1998). He was fired April 26, 2014, and served as special adviser to New York Islanders general manager Garth Snow during the 2015-16 season.
After: Hired by Vegas owner Bill Foley on July 13, 2016, and was responsible for building the team that set numerous NHL records for first-year teams. Vegas won the Pacific Division with 109 points and 51 wins.
Before: One season after being named a finalist for the Jack Adams Award as coach of the year with the Florida Panthers in 2015-16, Gallant went 11-10-1 and was fired Nov. 27, 2016, after a 3-2 loss against the Carolina Hurricanes.
After: The Golden Knights hired Gallant as their first coach April 13, 2017 and haven't looked back. He led them to a 51-24-7 record, the division title and has an 8-2 record through the first two rounds of the playoffs. Gallant is a finalist for the Jack Adams Award.
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