in underwater object manipulation and marine environment monitoring. Aquatic organisms and amphibians in nature provide great inspiration for the design and manufacture of novel underwater soft robots, which has attracted increased attention from the research community. [9][10][11][12][13] However, the controllability of the driving force still faces great challenges. Existing driving methods mainly include optical drive, [14][15][16][17] magnetic drive, [18,19] and electric drive. [20,21] Among them, optical drive has the highest controllability and tunability, so it is widely used to drive bionic soft robots in underwater operations. In addition, the use of soft smart materials increases the flexibility of bionic robots, reducing the need for heavy, and traditional rigid materials and sensing and actuation components. Most light-driven soft robots are made of liquid crystals [22][23][24][25][26][27] and hydrogels [19] that can undergo various deformations. Mechanical swing is important for converting input energy into continuous motion. Wang et al. reported a light-driven swing actuator composed of polyimide (Kapton) and azobenzene containing liquid crystal polymers. [28] The photoactive bilayer films were prepared with benzene-carboxylic acid containing monomer (M 6 BCOOH) and azobenzene-containing monomer (M 6 ABOC 2 ). When exposed to ultraviolet light, the double-layer film bends. The high modulus of the Kapton layer gives the film great resistance, so the film quickly returns to its resting position after UV light is removed. The double-layer strip exhibits mechanical swing behavior under continuous UV irradiation. Ma et al. also made a light-driven swimmer based on the above double-layer structure. [29] The swimmer bends quickly under UV light and recovers immediately after removing the light. When placed on a liquid surface, swimmers beat the liquid rhythmically, constantly propelling themselves forward.Snake is a kind of amphibian. Despite its simple body structure, it can realize a variety of locomotion forms, such as concertina locomotion and serpentine locomotion, to adapt to the changeable environment. So far, many researchers have studied the movement of snakes. For example, Yang et al. reported a snake-like biomimetic soft robot synthesized by three layers of graphene oxide (GO) and polydopamine. [13,[30][31][32][33] The soft material is capable of bidirectional deformation when near-infrared many researchers have studied the movement of snakes. [34] Wang et al. reported a snake-like soft robot consisting of a

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Due to the reversible ability of hydrogels to absorb and lose water, more and more researchers are applying hydrogels to the research of underwater robots. Sea anemones are soft marine creatures with simple structures and soft bodies, whose extended tentacles shrink in response to danger or capture of food. Inspired by sea anemones, we built a light-driven bilayer gripper to complete the process of catching and releasing. In addition, a bionic sea anemone actuator composed of a magneticdriven flower stalk and a light-driven flower was designed. Under the effect of an external magnetic field, the bionic sea anemone can wiggle, mimicking the sea anemone's drift through the water. The light-driven flower has superior programmability and fast response, simulating the contraction of sea anemone when stimulated. In addition, the flower stem of sea anemone can bend to capture prey. The flower stem of the bionic sea anemone introduced is photo-responsive, which can bend in different directions under unilateral light irradiation. This study combines light drive and magnetic drive, providing a reference value for underwater drive of actuators.