Daniel Sprong and Yanni Gourde each scored and Oliver Bjorkstrand for Seattle (5-4-2), who have won three of their last four games. Joey Daccord made his first start of the season and made 36 saves.
"It was real impressive the way we handled adversity in this game", Gourde said. "We trusted the game plan and we stuck to it, and we made it happen."
Tyler Toffoli had a goal and an assist, Nazem Kadri also scored and Elias Lindholm picked up two assists for Calgary (5-3-0), who have lost back-to-back games. Dan Vladar made 21 saves.
"At the end of the day, you have to be accountable", Kadri said. "You own it, you fix it, you watch the film. That's the name of the game. That's how the NHL works. It's a fast game out there. Not every single time it's going to go exactly the way you drew it up. You'd like to execute, but we're going to clean that up and that's certainly something we're capable of."
Kraken win first-ever game over Flames with lightning-fast comeback
Carson Soucy put the Kraken in front 1-0 as he shot over Vladar's glove from just inside the left faceoff circle off of a rush.
Nikita Zadorov tied the game 6:28 into the second period after gathering in a cross-ice pass from Toffoli, and Kadri put the Flames in front with a second-chance effort from the edge of the crease.
After a Calgary turnover in the neutral zone, Morgan Geekie tied things up on a two-on-one.
Toffoli scored 1:34 into the third period and 17 seconds later, Trevor Lewis beat Daccord blocker side to give the Flames a 4-2 advantage.
"Yeah, it wasn't great", Beniers said. "We probably would've liked to not give up two goals. I think we took a timeout and we kind of banded back together and were like 'alright we've got this, let's calm down it's not over yet, we've got 18 minutes left. Slowly but surely, we got one, and then 'Gourdo' made a great play on the PK [and] got another one and we were able to finish it. It was good."
Sprong cut it to 4-3, taking a pass from Alex Wennberg and one-timing it past Valdar with Seattle on the power play and Gourde tied it while the Kraken were shorthanded, stripping Kadri of the puck at his own blue line and scoring on a breakaway.
"I think we've got so much more confidence in this group", Gourde said. "Last year was last year. This year we have confidence in this group, and we know we can rally back and we know we have the skill to do it. It's a matter of just putting one shift together and then the next line is up. You just tilt the ice a little bit."
Beniers capped the comeback with his first career game-winning goal by taking a feed from Jordan Eberle and shooting over a sprawling Vladar.
"I was fired up", Beniers said. "I was smiling skating down the ice because you know Eberle's dangerous with the puck, whatever's he going to do. He ended up making a perfect play and gave me a wide-open net on the back side. That was great."