Exercise guide
Spell Caster
- Intermediate
- Compound
- Rep-based
- Core
The Spell Caster is a dynamic rotational exercise that builds explosive core strength and shoulder stability by forcing the obliques to accelerate and decelerate weight across the transverse plane.
Reviewed by the Crucible team · Updated June 2026
Muscles worked
Setup
- Stand with your feet slightly wider than shoulder-width apart for a stable base.
- Hold a light dumbbell in each hand with your arms extended down at your sides.
- Engage your core and maintain a slight bend in your knees to protect your lower back.
- Rotate your torso slightly to bring both dumbbells toward the outside of one hip.
How to do it
- Swing the dumbbells diagonally across your body and upward toward the opposite shoulder in a smooth, 'casting' arc.
- Exhale forcefully as you drive the weights upward, using your obliques to power the rotation.
- Inhale as you control the descent, bringing the weights back down across your body to the starting hip.
- Alternate sides by swinging the weights to the opposite hip and repeating the diagonal upward arc.
Form checklist
- Keep your arms mostly straight with a soft micro-bend in the elbows.
- Pivot your trailing foot slightly to allow your hips to rotate safely with your torso.
- Maintain a proud chest and avoid rounding your shoulders forward during the swing.
- Use your core to 'brake' the movement at the top and bottom of the arc rather than relying on momentum.
Pro tips
- Focus on the mind-muscle connection with your serratus anterior and obliques to stabilize the weights at the peak of the movement.
- Imagine you are drawing a large 'X' in the air with the dumbbells to ensure a full range of rotational motion.
Make it harder
- Increase the tempo of the 'cast' phase while significantly slowing down the eccentric lowering phase.
- Pause for two seconds at the top of the arc to challenge your anti-rotational stability.
Frequently asked
- What muscles does the spell caster work?
- The spell caster primarily targets the abs, deltoids, and obliques, and also works the lats, pectorals, and serratus anterior as secondary muscles.
- What equipment do you need for the spell caster?
- The spell caster uses dumbbell.
- Is the spell caster good for beginners?
- The spell caster is rated intermediate. Build a base with simpler variations first, then progress to it with light load and strict form.