It's a fantasy role-playing game.

DM: You are Tiberius Stormwind, a dragonborn sorcerer . You are the member of the famous group of adventurers. Previously, The party, after essentially forcing this individual to reveal themself, the rakshasa fled through a tunnel underneath its room into a long subterranean tunnel fraught with traps that were set to protect it. The party managed to avoid these rather deftly until the steady decline of the hallway, combined with the increasing moisture and scent of refuse, caused a slick surface and our fantastic cleric, Brother Kash, Kashaw, slipped and fell down.
DM: All right. Next up is the otyugh, who is extremely unhappy with how that went down. (growls) You now see as it pulls from the front of its body one giant backwards-looking elephant leg that steps into the front of the material, a second one, forward. It pulls itself completely out of the pile, and you can see a third one, like a giant tripod. These thick legs carry it forward. It is going to do a bite attack and a tentacle attack on you, and a tentacle attack on Keyleth, as you're the nearest to it. So as it rears back with its mouth, this giant maw opens with all these nasty jagged broken teeth, and the smell that comes out of its mouth is horrifying, even for your experience as a dragonborn. That would be... 18 to hit.
Player: Did you roll at disadvantage?
DM: Why would I have disadvantage?
Player: Cloak of Displacement?
DM: Oh! Good call. Oh, that's even higher. 19. But thank you for the reminder; that's good to know.
Player: AC is 18.
DM: So it hits.
