It's a fantasy role-playing game.

DM: You are Keyleth, a half-elf druid . You are the member of the famous group of adventurers. Previously,  The group of adventurers, Vox Machina, had found themselves in the Feywild, intent on discovering another one of the Vestiges of the Divergence, one of the many artifacts that they hope will aid them in their struggle against Thordak the Cinder King and the rest of the Chroma Conclave. They've defeated two of the members, three still remain, Thordak being the seeming powerhouse head of that troupe.
DM: No, Vax is in the next river over. Percy is about maybe 20 feet from you, but is quickly being rushed down the river.
Player: Vax is? Or Percy?
DM: Percy.
Player: Okay, so first, I'm going to Control Water. I'm going to stop the flow of current and see if I can get it to burp out Percy.
DM: Okay. Just pat it.
Player: I'm going to burp the river.
DM: (shushing) It's okay, Gilded Run. It's okay. All right, perfect. So you see this influx and see Vex get thrown out of the river. You see Percy's hand get pulled back under as the river pulls him along at a very fast speed. You concentrate, and as you put your fingers forward, you see the rapid river begin to slow down at a certain point, and it's almost like an invisible dam gets held up as the waters continue to flow out and carry him a little bit further. It slowly descends to leave him on an empty bank of water as the rest of it slowly seeps to a much lower level. You catch your breath, Percy. However, I need you to make a wisdom check, as this is a very powerful, magically-enforced river, and it's currently combating the strength of your spell. This is Keyleth. She's making a wisdom check.
