Simplest - Escaping from God's dungeon if you swore in Quest for the Golden Eggcup
Spoiler:You just dug in the sand.
Most Obscure - Escaping from God's dungeon if you swore a second time in Quest for the Golden Eggcup.
Spoiler:Digging in the sand just revealed.... more sand. You had to work out a secret password to escape.