Context: Our party returns to a fishing village after exploring a cave hideout to find the village under attack from a demon (that we just freed from said cave) setting it on fire. We end up battling him to help get the citizens evacuated. Down the line we do enough damage to where he’s fairly injured but we were at a disadvantage.
Two of our members got seperated and our barbarian had no means to hit a flying enemy. Our two rangers couldn’t hit him due to disadvantages from smoke and (the best part) our wizard Schmeckle had only one spell slot left.
Barbarian: Schmeckle we have to stop him now! Do something!
Schmeckle: I can’t! I have NO spell slots left to use.
DM: Actually you have one left.
Schmeckle: Yeah but there’s nothing that I can use to damage him… Wait… okay you guys are gonna hate me for this but –
Ranger: But what?
Schmeckle: Alright. I will cast SLEEP on the demon.
DM: Alright, roll 5d8 to see if it takes effect.
Schmeckle: (Rolls a successful spell)
DM: Holy shit, okay. With desperation you cast sleep and effectively cause the demon to lose consciousness and falls heavily to the earth, (rolls damage upon impact), and dies on impact.
Everyone in the party: Holy shit.