Soft actuators have opened compelling new opportunities in the fields of manufacturing, robotics, and medicine. [1] Because of their conformal and mechanically compliant nature, actuators made of soft materials allow for safe interactions of robots with humans and provide an attractive platform to interface flexible electronics with human skin and tissues. [2][3][4][5] Potential applications that can benefit from these features include robots for manipulation of delicate objects, [6] exoskeletons for motion rehabilitation, medical prostheses, [7] surgical aid devices, [8,9] and intelligent reconfigurable matter in general. [10] In many of these applications, it is desirable to minimize the energy required for actuation, enhance actuation speed, and enable untethered autonomous motion.Among the several possible types of devices and actuation modes, [11][12][13][14][15][16][17][18][19][20] magnetically responsive actuators are particularly interesting, because they are fast, contactless, and are driven by magnetic fields that can be safely used in humans. [21] Contactless control allows for the manipulation of untethered devices in confined spaces, which is crucial for minimally invasive medical devices. [22] Making soft objects magneto-responsive is also a promising approach in the ongoing efforts to create devices with complex output motion driven by a simple single input. [23] For example, recent research has shown that the soft objects with tunable local magnetization patterns can undergo complex motions, such as crawling, rolling, and jumping when activated with an external magnetic field. These magneto-responsive soft materials have so far been produced in simple planar geometries using NdFeB microparticles that are pre-magnetized using magnetic fields higher than 1 T. [19,24,25] Although the magnetization of NdFeB particles using these approaches prevents de-magnetization of the actuator, the

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