Undertale but weird

The Barrier of Calyphor is an arcane phenomenon that serves as a protective shield around an ancient city, shimmering with a radiant blue glow. It hums with magical energy and is rumored to shift shape, forging a dynamic connection to the elemental planes. Adventurers seek to unravel its secrets, while the city's defenders harness its power to repel malevolent forces.

A vast shimmering barrier encircling the ancient city, radiating a soft blue light and inscribed with glowing runes, under a starry night sky.