Hunter McDonald
While it could be wild to say a player who has yet to play in the NHL could make an impact, it's not impossible for Hunter McDonald. The team has long been a fan of his style of play and the compliments continued to flow at development camp. McDonald plays an old-school style as a bruising defenseman.
He debuted with the Phantoms after two years at Northeastern. While that is where he is likely to play a majority of the season, debuting with the Flyers doesn't seem far fetched. The Flyers have plenty of offensive defensemen on their blueline, but lack a truly physical player. But McDonald can do more than just hit players.
As Nick Schultz said, McDonald's skating is what sets him apart from the old-school defensemen. He's able to get up the ice and involved in the offense. And for a player who plays a physical brand of hockey, he only had 32 penalty minutes during his final collegiate season. In 11 games with the Phantoms, he had 12 penalty minutes. Being able to toe the line with his aggression is an important thing to learn.
Again, he likely wouldn't make a huge impact at the NHL level to start. But the Flyers are very much interested in his potential. If he can show that he has the ability to translate his game, they may find a spot for him during the season.