Giant fantasy fly agaric mushroom, ...

Giant fantasy fly agaric mushroom, scaled to function as a huge multi-floor building. Create a massive thick pale stem with an organic, crooked, uneven silhouette: naturally bulging, tapering and widening unpredictably as it rises. Avoid cylinders, symmetry, straight walls and stacked circular layers. The stem must be hollow and spacious inside. Use mushroom stem, calcite, bone blocks and stripped pale oak logs blended naturally. Above it, create an enormous wide red mushroom cap that dramatically overhangs the stem, with a thick curved underside and irregular drooping edges. Use red concrete with large natural white patches. The cap should feel oversized and heavy compared with the stem. No doors, windows, floors, stairs, furniture or decorations. Only generate the hollow mushroom shell.