Quaternions are the gold standard for avoiding gimbal lock, but they’re not the only trick. You can still use properly ordered Euler rigs with constraints that lock the problematic axis, or even dual‑quaternion skinning to keep joints from twisting awkwardly. In practice, I’ll start with quaternions for the heavy lifting, then add axis locks or helper constraints to keep the motion clean. If you’re not careful with naming and layer structure, even a perfect quaternion setup can become a headache.

The biggest slip‑up is usually the constraint target itself – if it’s in the wrong space or its pivot is off, the whole rig starts to jitter. I’ve seen a dozen times where a helper constraint’s weight gets reset to zero or its order is swapped, and suddenly the IK chain goes wild. Even a single misplaced “Parent” instead of “Aim” can throw the whole system off, so I double‑check the target’s transform and the constraint hierarchy before locking anything in place.