Callahan, 25, appeared in 66 games with the American Hockey League's (AHL) Grand Rapids Griffins last season, posting 43 points (16G, 27A) and 57 penalty minutes. He also recorded 16 points (6G, 10A) and 18 penalty minutes in 19 playoff games, helping the Griffins capture the Calder Cup.
The Whittier, California native has accumulated 186 points (94G, 92A) and 422 penalty minutes in 365 career AHL games.
Stanton, 27, appeared in 48 games last season with the American Hockey League's San Antonio Rampage and Cleveland Monsters, accumulating 12 points (2G, 10A) and 69 penalty minutes. Stanton has appeared in 332 career AHL games, registering 88 points (15G, 73A) and 470 penalty minutes.
The St. Albert, Alberta native has played in 120 career NHL games with the Chicago Blackhawks, Vancouver Canucks and Washington Capitals, recording 27 points (4G, 23A) and 71 penalty minutes.
Downing, 25, appeared in 59 games last season with the American Hockey League's (AHL) Iowa Wild and Tucson Roadrunners, accumulating 26 points (9G, 17A) and 15 penalty minutes.
The Abbotsford, British Columbia native has played in 120 career AHL games, registering 70 points (28G, 42A) and 43 penalty minutes.
Ferlin, 25, has appeared in 78 games over three seasons with the AHL's Providence Bruins, posting 34 points (17G, 17A) and 69 penalty minutes.
The Jacksonville, Florida native has appeared in seven career NHL games with the Boston Bruins, notching one assist.
Rattie, 24, appeared in 22 games last season with the AHL's Chicago Wolves, notching five points (2G, 3A) and two penalty minutes. He has accumulated 141 points (71G, 70A) and 79 penalty minutes in 215 career AHL games.
The Calgary, Alberta native also appeared in five games with the Carolina Hurricanes last season, posting two assists. Rattie has played in 35 career NHL games with the St. Louis Blues and Carolina Hurricanes, registering 10 points (4G, 6A) and six penalty minutes.