That’s an intriguing idea. Real mushrooms don’t sprout overnight, they need a substrate, moisture, and a steady temperature. If you want the set to look like a sudden mushroom forest, think about a base of rich, damp organic matter—maybe a thick layer of compost or a pile of decaying logs—and let spores settle in that environment. The growth will be slow, so you could stage the scene in stages: start with a few small caps, then gradually add larger ones as the “set” develops over a week or two, or simply use practical effects to simulate that slow build. Keep the lighting soft and green‑ish, like filtered light through a canopy, and use the natural textures of bark and soil to give the space an authentic feel. I’d recommend filming from a low angle to capture the forest floor vibe and letting the audience feel the quiet, patient expansion of the mycelium. That way the stunt feels grounded in the quiet rhythm of nature, rather than chaotic magic.