A Mandelbulber render using Hybrid Fractal (Menger Sponge [3i] + Kaleidoscope IFS ]1i]) along with some water ("primitive shape").
PS Note : It's 3 separate renders layered in photoshop, the bottom one with most of the work, layered on top by a volumetric fog render (without ambient occlusion) and another layer without depth of field adjustment at a very low opacity)

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