Surrealism was something boundless, a high-level law in the world. Not only does a world have spatial law, it has surrealism law as well. This was what they meant in buddhist sayings that an entire world could fit into a mustard seed.
Using this law, an entire world in a seed could hide as a speck or a particle in a boundless universe.
Surrealism law contains mystical capabilities. It was just like now when the heaven chosen from the Skymist Immortal Empire attacks, motes of particle-size light could transform into gigantic demonic elephants, radiating true terrifying might that could destroy the world.