Dave in the Cave is a new point and click adventure escape game from timefall. Apparently, there will be an earthquake and worse is that Dave is in a cave - a dangerous place to be in times of quakes. Help him find the diamond and find a way out before the earthquake comes around shaking places down to rubble.
You might be stuck at this game that's why you are here, so let me point you to this
Dave in The Cave walkthrough which demonstrates how to beat the game, but it contains major spoilers so use it at your own risk.