It's a fantasy role-playing game.

DM: You are Fjord, a half-orc warlock . You are the member of the famous group of adventurers. Previously,  However, upon noticing that some of the buildings on the eastern side of town began to light up with what appeared to be flame, you began to approach rather rapidly, seeing members of the city's citizens fleeing, screaming, and apparently there seemed to be some sort of attack. Upon going into the town, you realized that a number of these buildings were being set fire by an incursion of Gnolls.
DM: The one that's now taken a crossbow bolt to the throat and has taken a Guiding Bolt, this giant blast of light explodes around this gnoll as it yelps and it encompasses its torso with this glittering light. Now the next attack against it has advantage. It is super hurt, but still standing. You're making your attack.
Player: Yeah, I rolled the first one, which was a 24, but with advantage. That's less, so 24.
DM: You were attacking the other one, so you do not get the benefit.
Player: Oh yeah, I'm sorry. 24 for the first roll.
DM: Still hits, go ahead and roll damage on that one.
Player: Oh balls, that's--
DM: What are you using?
Player: Eldritch Blast.
DM: It's a d10 for damage. That's a d12.
