Dimensional Key in Stone Age: Anime Portal Quest

An anime-style illustration set in the Stone Age: a brave hunter (or hunter-girl) stands in a torch-lit cave, gripping a glowing dimensional key carved from bone and obsidian with rune-like engravings that pulse electric blue. The key opens a swirling portal that folds space, revealing stars and distant landscapes. The cave walls are covered in primitive cave paintings and glyphs. The character wears a fur cloak, leather straps, and a stone dagger, with large expressive anime eyes and a dynamic, energetic pose. Warm amber torchlight clashes with the key's cool glow, casting dramatic shadows on rough stone and drifting dust motes. In the background, jagged rocks and distant mammoth silhouettes add depth. The art style is crisp anime with cel shading, vibrant color contrasts, and a sense of immediate adventure.