A towering dark fantasy castle coloseum inspired by ancient Greek necropolis architecture. The base is a wide, circular marble platform cracked by age, surrounded by 12 tall obsidian Doric columns that lean slightly inward. At the center rises a spiraling hexagonal tower made of black stone and silver-veined onyx. Its windows are deep, narrow slits glowing with soft blue light. The upper tier is crowned with a fractured crystal dome hovering just above the roof via ancient levitation glyphs. The entrance is guarded by two massive serpent-statues carved from basalt. Vines of bronze twist along the columns like veins. Every surface is engraved with runes predicting forgotten prophecies. Designed with real structural balance, printable modular design, no floating geometry., #arch#

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