"Legends speak of a Colossal Cave that extends deep underground, so twisted by time that its passages shift like the sand under which it lies... the Cave is said to be filled with fabulous treasures, but also incredible danger!"
Spelunky is a cave exploration / treasure-hunting game inspired by classic platform games and roguelikes, where the goal is to grab as much treasure from the cave as possible. Every time you play the cave's layout will be different. Use your wits, your reflexes, and the items available to you to survive and go ever deeper! Perhaps at the end you may find what you're looking for...
Don't be afraid to die! But also don't be afraid to live! Happy Spelunky-ing!