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enable real-time computed tomography (CT) imaging guidance, allowing precise magnet-driven navigation
to target tissues for localized photothermal or magnetothermal ablation therapy.

MLM slurry-based soft robots
As the content of embedded magnetic particles further increased (typically > 10 wt%), the fluidity of the
MLM decreased significantly, leading to a more slurry-like consistency. This higher viscosity improved the
structural stability of the soft robot under deformation, allowing it to maintain complex shapes without
collapsing [61,90] . The transition from a low-viscosity droplet state to a viscoelastic slurry enabled programmable
shape-locking behavior, where external magnetic fields or force could induce temporary deformations
that were retained upon field removal or force.

MLM slurry-based soft robots bridge the gap between solid and liquid states, combining the structural
stability of solids with the dynamic adaptability of fluids. Moreover, the increased magnetic particle
concentration also strengthened magneto-mechanical coupling, enhancing the magnetic response
performance. With these unique properties, MLM slurry-based soft robots demonstrate remarkable potential
for multifunctional applications spanning object manipulation, flexible electronics, and biomedical
engineering.

For object manipulation, the MLM slurry composed of Fe particles and Ga was demonstrated as a magnetic
robotic gripper [Figure 10A] . By coupling the switchable interlocking force during phase transition with
[59]
magnetic responsiveness, the MLM slurry can achieve strong, reversible, and nondestructive magnetic
manipulation of arbitrarily shaped non-magnetic objects. The interlocking force exhibited a difference of five
orders of magnitude between the solidified and melted states. In addition, leveraging Rosensweig
instability-induced surface spike formation, the MLM slurry robotic pillar achieves magnetically switchable
adhesion [Figure 10B] . In the absence of a magnetic field, their intrinsic fluidity ensures gentle, conformal
[110]
contact for damage-free pickup, while magnetic stimulation triggers rapid spike formation and stiffening,
enabling reversible adhesion reduction and noncontact ejection. This instability-driven mechanism allows
deterministic transfer printing of fragile 2D and 3D objects.

Benefiting from the low fluidity and surface tension, the MLM slurry shows better printability than the pure
LM, promising for the fabrication of flexible electronics. As the content of the Ni particles increased, the
adhesion of the MLM slurry to the substrate was enhanced, allowing stencil printing [Figure 10C] [111] . To
prevent the LM leakage, hard magnetic particles of NdFeB were introduced into the LM, which can form a
tight porous structure to immobilize the LM after magnetization . Alternatively, heat treatment facilitated
[76]
the formation of intermetallic compounds in the solid phase, thereby enhancing structural stability [Figure
10D] [112] . Utilizing both the electroconductivity and magnetic responsiveness, the patented MLM circuits
showed the integration of electric sensing and magnetic actuating. For example, the applied magnetic field
not only actuated the MLM slurry-based coil robot but also induced a measurable voltage [Figure 10E] ,
[61]
whose amplitude and frequency served as effective indicators for characterizing the magnetic actuation
performance.

Furthermore, the MLM slurry was also found to have promising applications in biomedical engineering. The
applied magnetic field enables precise regulation of the Young’s modulus, demonstrating reversible
modulation across three orders of magnitude (kPa-MPa) with field intensity variation. This phenomenon
originates from the formation of magnetic field-induced chain structures of Fe particles, which enable the
rapid and reversible transition between soft and rigid states. Based on this, the MLM slurry-based needle can
serve as a mechanically adaptive bioelectrode capable of matching diverse tissue stiffnesses, thereby
minimizing trauma and scarring during implantation [Figure 10F] . In another work, the MLM
[90]