Be me a new gm.
Spend all this time planning this session and the boss.
Gets to the final room that’s blocked by a giant stone slab.
Barbarian: “I wanna try pushing it in.”
GM: “… It’s a GIANT stone slab … Like twice your size…”
Barbarian: “I got this”
GM: “sure why not. Roll for it”
Pushes the slab over and they proceed to find the boss.
Cleric (barbarians brother): “I wanna convince the boss to just leave.”
GM: “… Well talk and roll it”
Cleric proceeds to talk to boss and gets 3 Nat 20s in a row.
Boss: *looks at barbarian, looks at door, looks at party* “you guys aren’t even worth my time.”
The boss proceeds to leave and I flip the table.