However, upon application of a low UV intensity light (to prevent 3D motion), we find that the microswimmers swim in the direction of the magnet. This shows the ability of a small quantity of Fe 2 O 3 magnetic nanoparticles to orient the microswimmer in a specified direction, in turn imparting control over their motion. Therefore, our modular approach to TNA enables the scalable fabrication of multi-functional Janus microswimmers with decoupled steering (magnetic) and propulsion (light) mechanisms, similar to the "colloidal-surfers" first demonstrated by Palacci et al., and distinguishing itself from more typically studied systems where translational motion and steering are both controlled by the imposition of an externally applied magnetic field. Directing the orientation of the hybrid magneticcatalytic caps could also be used to rectify their orientation and thus provide a further degree of control over microswimmer speed. We furthermore expect that the ability to modify the base photocatalysts with various co-catalyst nanoparticles previously outlined will open the door to a combinatorial range of new microswimmer architectures and behaviours, which nonetheless will demand future detailed mechanistic studies.