Build a massive 150-block-wide circ...

Build a massive 150-block-wide circular ancient proving grounds arena inspired by a forgotten civilization. The arena should feature a large 45-block central boss platform with an ancient altar, surrounded by multiple circular combat rings connected by wide paths. Add four massive cardinal towers (north, south, east, west) connected by grand staircases leading into the arena. Surround everything with a 20–25 block tall coliseum wall filled with ruined arches, battlements, statues, and broken towers. Include plenty of cover using ruined pillars, collapsed walls, and elevation changes while keeping all combat areas open and easy to navigate. Make the build perfectly symmetrical, prioritize gameplay over decoration, and leave large open areas for future boss mechanics and scripted events.