It's a fantasy role-playing game.

DM: You are Grog Strongjaw, a goliath barbarian . You are the member of the famous group of adventurers. Previously, She tests the roots of the cursed tree for any illusory magic, but it is solid and real. you attempts to level up the Titanstone Knuckles by destroying the kitchen, much to Scanlan's consternation.
DM: Yeah, where when it hits you you can use your reaction, but you used your reaction to get an attack of opportunity, so you still hit him.
Player: Oh, that's true.
DM: But essentially, they don't have to do that now. As long as they hit you, you can use your reaction to just hit them back.
Player: Hit them back.
DM: So yeah, as long as you stay within melee--
Player: As long as I'm within five feet. That count on his two hits against me?
DM: I mean, you can only do it once, because you only get one reaction.
Player: One time. Okay.
DM: And you technically already hit him with that.
Player: That's true.
DM: Same thing, so you used your attack of opportunity, so you can do that whenever anybody hits you.
