What exactly does a rank difficulty change in the world of trials? The monsters stayed the same, and the environment didn't change a single bit. Apart from the simplest missions turning into a story quest, the only thing that wasn't noticeable. Was the chance of the flow of mana, with the authority of the Game masters, they can change this at will. But that doesn't ask the question why am I right? Well, I'm getting there, mana is the source and the origin of monster spawn rate. So if you ever see a horde of monsters in a singular area then im sure it has a ton of mana build-up
[System: You've been transported to an area that your ally has previously marked. Your location has changed from the conquered city to the edge of the biome. Alert: There seems to be a lot of mana building up on this side of the map. Please turn around, this is not a place where you can escape solely on your talents]