It's a fantasy role-playing game.

DM: You are Vex Vex'ahlia, a half-elf ranger . You are the member of the famous group of adventurers. Previously, He and his party were left for dead, but his patron goddess, Tiamat, kept him alive. He offers a temporary alliance with Vox Machina against Vecna.
DM: Okay. First off, make a perception check as you glance out to see how close you are to the nearby wall.
Player: 30.
DM: 30, okay. You notice you're on a different part of the city than you were previously. If the city's moving forward, if you consider the direction that the titan is traversing forward, you guys were to the back and right side of Thar Amphala. Like a clock; if twelve o'clock is where it was traveling, you guys were around four or five o'clock. Looking now at the layout of the city, you're closer to 11 and 12 right now. And you're maybe about 200 feet from the nearest wall. You can see the curvature of the dome is pretty striking from your current position. And you can see the pulses, the waves. Imagine like a reverse waterfall of energy shooting upward. And every now and then, there's a burst.
Player: Does it look like there's an area that the pulses are brighter, along the wall?
DM: Yes. You do see the pulses aren't universal. There are certain locations, about six of them throughout the city, that you occasionally see them (bursting), and they spread out.
Player: Are we close to one of those pulses?
DM: You can maneuver there. It's not directly behind you, but you can eventually get to that location, yeah.
