Max Pacioretty had a power-play goal and two assists for the Golden Knights (4-2-0), who went 3-for-3 with the man advantage after starting the season 3-for-17.
"We want to be capitalizing on the power play, or at least getting some sustained pressure," Pacioretty said. "The last couple games we haven't capitalized on it, but I thought tonight we] had some good zone time, we were moving the puck around, and guys were finishing. That's what you want from your power play."
***[WATCH: [All Golden Knights vs. Kings highlights]*
Marc-Andre Fleury made 36 saves playing in his 804th NHL game, which passed Harry Lumley for 15th place among goalies in League history.
Dustin Brown and Austin Wagner scored for the Kings (2-3-0), who allowed at least five goals for the third time this season. Jonathan Quick made 31 saves in his first start since allowing an NHL career-worst eight goals to the Vancouver Canucks on Wednesday.
"He's still that good, in my opinion," Kings coach Todd McLellan said of Quick, who is 0-3-0 with a 6.44 goals-against average and .793 save percentage. "When you're the goaltender, when you're the pitcher, when you're the quarterback, all eyes are on you. It's as simple as that. He's the last line of defense for our mistakes, and we made our share of them."
Stastny gave Vegas a 3-1 lead at 14:51 of the second period, redirecting Pacioretty's pass in the slot. He extended the lead to 4-1 at 17:00 by finishing a tic-tac-toe passing sequence in the left circle.