Cody Corbett, Michael St. Croix, Keegan Lowe and Brandon Baddock also scored for Edmonton (21-7-5).
Tyler Stahl and Steven Hodges scored for Victoria (17-14-2).
Stahl opened up the scoring at 5:45 of the first, converting a point shot through traffic that beat Oil Kings' goaltender Tristan Jarry over the left pad.
Edmonton's Corbett evened things up at 2:02 of the second with a rocket from the high slot over the glove of Victoria netminder Patrik Polivka.
Victoria replied quickly on a turnover as Hodges cut into the middle and rifled a shot past Jarry to make it 2-1 Royals at 2:56.
St. Croix tied the game at 5:24 of the second with a one-timer into the top corner past Polivka while on the power play.
Foster finished off a wraparound at 7:50 to put Edmonton ahead 3-2.
Lowe buried a shot off of a goal-mouth scramble at 15:26 to give Edmonton a 4-2 lead and Baddock added Edmonton's fifth goal 34 seconds later, which led to Polivka being pulled for Coleman Vollrath.
Jarry stopped 24 shots for the win as Polivka picked up the loss after allowing five goals on 23 shots. Vollrath stopped all six shots he faced in 24 minutes of relief.
Edmonton went 1 for 5 on the power play while Victoria failed to score on four chances with the man advantage.