Yep.Get them to dig, farm (giant mushrooms, hamsters, grubs), build elaborate traps ("squish" trap. Takes three stone chunks, if I remember correctly), cook, breed (no immigrations), and bury the hats of all their dead enemies before they actually tend to their own.
One of the main things that annoyed me was that the Urwald maps didn't have any metal in them. I dug and I dug and I dug, but not so much as a scrap of ore came out.
There are four "worlds" in Diggles. Urwald, which is a verdant and mossy area that sports a calm environment, prime mushroom-growing conditions, and generally lots of wild hamsters and grubs. It also will often have several pools of water in some places. This is the hippy/laid-back area.
Then there's the sulphur zone. Everything has a disgusting dark-yellow color, vile alien flora grows rampant, and small bursts of flame pop up from time to time. However, "base" ores such as iron and gold are very common, along with large amounts of coal. This is the industrial area.
Next we get hell. The stone takes on a blood-red tint, and very few things grow. Vile monsters roam the caverns, waiting for a chance to sink their teeth into dwarven flesh. Ores are very common however, as is coal. This is the bastion-against-evil area.
Finally, crystal. The air is filled with a perpetual fog of sorts, and the whole world takes on a dark blue color. Vast crystalline formations grow from the walls and lend the area a very strange yet mystical atmosphere. Coal is hard to come by, but it contains a smattering of every ore in the game. It is also the only area (so far as I know) where you can harvest the crystal, and in great quantities. Crystals are used in making the most expensive and lavish accommodations in the entire game, as well as certain other interesting things.
But beware, not all the crystal is so docile as to wait around for your harvesting efforts to destroy them. Strange crystal spiders make this area their home, and although they appear delicate and filled with unearthly grace, their razor-sharp appendages can make mincemeat of an unprepared dwarf.
Also, don't even try hunting hamsters without a slingshot.