Note: Don't waste any small bombs -- you'll need them all.
Light the first bomb at A where you find it, to get rid of the monk below. You can then either battle the monk in the lower left, or take teleporter B to safety and come back later. If you take the teleporter, There's a trapdoor at C so you can escape.
Grab at least 1 small bomb, then make a trip to get the large bomb D and treasure E. Start at the far right, and dig into the room with the large bomb. Light a small bomb at F to get to treasure E and out. (After 148 levels, you should be able to dodge the monk pretty easily, right?) There is also a bomb buried at I, but you should ignore it.
To get treasure H, dig through K, light a bomb at G and teleport to safety before it explodes. Then quickly return to G, grab treasure H, and run back to G. Stay at G until the monks are a safe distance away.
To get the the exit doors, light the large bomb at point J. (Move the key out of the way first.) You can do this at any time, and once you've done it, you can get the befuddlement gas, as the teleporter beside it will stop functioning. It's probably not worth the effort, though.
Once you have all the gold, you can get the other large bomb (there's a trapdoor below it), and then use it to get the red key. If you followed directions, though, you won't need either of these.