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, you shoots a Lightning Arrow at the prone guard currently being mauled by Keyleth the Dire Wolf. The electricity courses through him, and Keyleth and the invisible Sir Kerrion each receive a small shock as well.
DM: Okay, 19. As it snaps and it bursts, the electricity shockwaves out, he shakes and on the ground takes in the effect. The blast seems to-- is it half damage if they make the save?
Player: To the little prone guy?
DM: No, it's to anybody within radius.
Player: Anybody within radius takes 1d8 if they make the save and then 2d8 if they fail.
DM: Okay, so roll 1d8.
Player: One.
DM: Okay. So one damage to you, and one damage to Sir Kerrion.
Player: Oh.
DM: You see a spark of energy around the invisible form as it wavers in place.
