Near the beginning of Act 2 while I was spelunking in the desert, I came across a cave that someone was standing outside of. He spoke of there being a treasure buried inside, but when I entered the cave, it was being timed. I only had a set number of minutes to reach a secret room I believe. Well I didn't make it to the end and the NPC said "the cave will be closed for another milennia" or something to that effect.
Does anyone know what cave I'm talking about and when/how to re-open it? I would like to try and get the treasure he spoke of.