The Mine Shaft


Hint: Not all things are visible.

Full Solution:


There are also powder keg generators! First, find the keg generator. There is one keg hidden in the wall behind the generator (green "X"). Bring that keg out and push it down the conveyor to destroy the flame at the end of the conveyor. Stop the conveyor and quickly go to the room in the lower left and push the boulder to destroy the remaining keg. Pick up any coins along the way. The generator has now generated 4 more powder kegs. Step on and collapse the 2 bridges along the right. Next, stop the conveyor again and carefully enter the room to the north to pick up more coins. Now simply push powder kegs out to fill the ponds to retrieve the remaining coins.