Campbell, 27, has played 454 games over seven seasons in the AHL, totaling 16 goals, 73 assists and a plus-27 rating with the Portland Pirates and Manchester Monarchs. The Caledonia, Ont., native split the 2014-15 season between Portland and the Arizona Coyotes, recording 3-9-12 in 40 AHL contests and picking up one assist in 33 NHL games.
A third-round draft pick by the Kings in 2008, Campbell played nearly six full seasons in the AHL before making his NHL debut with Los Angeles in 2013-14.
Miller, 21, played the last four seasons in the Ontario Hockey League. The Orangeville, Ont., native set career highs in goals (19), assists (36) and points (55) in 65 games with North Bay in 2014-15.
Clapperton, 21, was a 2013 fifth-round draft selection by the Florida Panthers. He completed his junior career with Rimouski (QMJHL) last season, scoring a career-best 35 goals and adding 41 assists for 76 points in 61 games. He added 25 points in 18 playoff games to help Rimouski to the league championship.
Findlay, 22, made his AHL debut with the Marlies in 2014-15, recording one goal and three assists in 15 games. He spent most of the season with Orlando (ECHL), where he notched 18 goals and 23 assists for 41 points in 45 contests.
Watling, 21, recorded two goals and one assist in 29 games as a rookie with the Marlies last season, and added 11 goals and 14 assists for 25 points in 24 ECHL games with Orlando.