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, Grog slams his war axe into the roof, splitting it open. Grog slides down into the room below, Pike jumping onto his foot and falls to the side.
DM: (explosion) He gets shot in the back of the shoulderplate, you hear it ricochet and a little bit of blood begins to streak off the back of his head. He looks over his shoulder with an angry grunt, you can see now this dwarf, who's still swelling in size. It looks, (growls), an angry nostril flare. You, have your bow ready?
Player: I wanna do Lightning Arrow on the guy attacking my brother.
DM: That guy there?
Player: Yeah.
DM: Okay, go ahead and roll to attack.
Player: Ugh, I don't think I hit.
DM: What'd you roll?
Player: I had rolled a four.
DM: A four, you had a plus 11 to hit, it's going to be a 15, unfortunately you miss. The arrow streaks past. Yeah, the arrow just ended up striking the wall back here and (explosion) arcs lightning throughout the wall, unfortunately does not--
Player: I Hunter's Mark him anyway, just for future stuff.
DM: You used your--
Player: That was a bon--
DM: You used your bonus action to cast Lightning Arrow.
Player: Oh! So I get a regular attack now?
DM: Well, that was part of your regular attack, like your next arrow you fired.
