Build a frozen boss arena: a circul...

Build a frozen boss arena: a circular open battlefield, 40 blocks in diameter, with a flat floor of packed ice, snow blocks and blue ice patches. Surround it with a ring of jagged ice spikes and frozen pillars (packed ice + blue ice, 8-15 blocks tall) forming a natural wall. Keep the entire arena open to the sky - no roof. Place a slightly raised circular platform (3 layers, 7 blocks wide) at the exact center. Add glowing accents with sea lanterns embedded in the floor and end rods on pillar tips, aurora-like. Scatter small snow drifts and cracked ice details. No water, no lava, no trees. Winter palace ruins aesthetic.