Oblique/Serratus Triset
While the obliques and the serratus may be known for their physical appeal as you lean out, they also play a large role in stabilization during movement. This is a functional triset I use to target these areas, and is usually added at the end of leg training days.
Single Arm Overhead Carry- Holding a dumbbell or kettlebell overhead in one arm, walk the distance of the gym down and back. During this movement you want to make sure you are keeping your spine straight, resisting leaning to one side. You also want to make sure your shoulder is locked in place, reaching the dumbbell as high as you can.
Front Rack Kettlebell March- For this movement you will want to use a heavy kettlebell or dumbbell, placing it in the front rack position on one shoulder only. With the kettlebell in position, you will perform 20 marches in place, bracing your core and driving your knee up. Repeat for 20 more steps with the kettlebell on the opposite side.
Oblique Band Pushdown- Wrap a heavy band around a pull up bar or top of cable crossover, grab the band with your arm at your side. Push the band down by performing a side crunch type movement. I like to place my fingers just below my ribs and imagine trying to squeeze them while you perform the movement. While very similar to a side bend, I feel this is a better alternative, as you are pushing down and resisting bad tension, rather than letting a DB pull you down.