Guys did I ever tell you about the time I completely accidentally ruined a professionally made campaign for Dungeons and Dragons thanks to a single roll

Please explain

Ok so we had to fight our way to the bottom of a castle to stop a group of cultists from summoning an Orc god to the world and we got there and the ritual was already going so I ran up to the god, who had already begun to manifest, and cast Finger of Death, which kills any target I touch if they fail a Fortitude roll. Since he was a god, he had a good constitution and would have certainly survived

Except the DM rolled a 1

and the god exploded