When you get past the first set of traps, there will be rocks near the area you pull the chain to deactivate the traps.
Have everyone in your group grab a rock and proceed to kill the lieutenant and two silver mobs. The rocks do a decent amount of damage and knocks back enemies that don't have the defiant stack.
Do the same for the Ranger boss and the Lovers. It works especially well against the lovers since they don't have the defiant buff, and you can just chain knock them back until they die.
Here's a video:
Ascalon Catacombs Story Mode: Rock Throwing Is Pretty Good - YouTube