Regardless of whether you've played other games like it, you'll find that Empire Earth is massive--more than most real-time strategy games would dare to be.
Empire Earth is a real-time strategy game that spans about a half a million years of human history, the last 200 of which take place 200 years from now. So if you're the type who appreciates ambitious game designs, then you've found one in Stainless Steel Studios' first game, which was conceived by the designer of the original Age of Empires. Actually, Empire Earth has a great deal in common with Ensemble Studios' highly successful Age of Empires series. Even the games' graphics look similar, though Empire Earth uses a fully 3D engine, unlike Age of Empires. Similarities aside, Empire Earth is a huge game to say the least--it's much more time-consuming and involved than the typical real-time strategy game, and its staggering variety of units is as impressive as it is intimidating. Real-time strategy is sometimes criticized for favoring shallow, action-oriented gameplay rather than strategic depth--but that's definitely not the case here. In fact, Empire Earth is best reserved for hard-core real-time strategy players who won't mind the game's less-than-stellar graphics and sound but will instead relish the ability to relive 14 different epochs of human warfare.
Empire Earth is clearly designed to appeal to those who enjoy Age of Empires II: The Age of Kings. Those familiar with Age of Kings should be able to jump right in and start playing Empire Earth, which borrows most of that game's controls, interface features, and even some of its keyboard shortcuts. As in Age of Kings, in Empire Earth, you must spend a considerable amount of time focusing on gathering various resources. All four of Age of Kings' resources have been appropriated for Empire Earth. A fifth resource, iron, has been added to further complicate the resource-gathering process. Most resources are found lying out in the open, in square-shaped deposits conveniently strewn about the map. Hunting for food also plays a big role throughout Empire Earth. All manner of realistic-looking 3D animals are there for you to hunt: cute giraffes, cute hippos, cute walruses, cute elephants, cute horses, you name it. Be careful, though--if you hunt too zealously, you'll wipe out the species. However, if you consciously let some animals live, offspring will appear, letting the delicate cycle of life continue for later exploitation.
Unfortunately, unlike in Age of Kings, there's no market structure that you can build to trade a surplus of one resource for another. This makes it all the more essential that you constantly weigh the importance of each individual resource in your short-term and relative long-term strategy and that you aggressively expand your territory to claim the resources you'll desperately need. If you're locked out of a particular type of resource, chances are that defeat will be close at hand. Then again, most units require only two out of the five resources, so you can focus your strategy accordingly or at least change your military spending to account for low quantities of particular resources.
Age of Empires II: The Age of Kings wasn't exactly a simple game--despite being more than two years old, it's still popular, thanks in large part to the sheer variety of strategies possible because of all the different units and playable factions. Empire Earth takes that game's recipe and doubles it. In fact, there's little denying that Empire Earth has by far the broadest scope and the greatest breadth of content of any real-time strategy game to date. From stone-age rock throwers, Roman chariots, medieval knights, and Napoleonic musketeers to World War I-era biplanes, World War II-era tanks, and 22nd-century giant robots, Empire Earth's variety of units is almost ludicrous. All told, there are more than 200 units in all, a number rivaled only by the impressive 1997 real-time strategy game Total Annihilation--but only if you count the additional units found in Total Annihilation's first expansion pack. Empire Earth also features a good variety of buildings and technologies, though these aren't quite as exhaustive as the unit options. In fact, many of the buildings remain the same throughout all the epochs.
Does the additional breadth and complexity of Empire Earth mean it's a better game than Age of Kings? No, of course not--you can actually have too much of a good thing, and Empire Earth is evidence of this. Using the default game settings, resource gathering is painfully slow. Not only that, but the costs required to advance from one epoch to the next are extremely high. It's theoretically possible to play a game of Empire Earth starting in the prehistoric epoch and work all the way on up through the nano epoch. But this would literally take hours upon hours. Fortunately, there are options available for optionally speeding up the gameplay, as well as a deathmatch mode that starts you off with plenty of resources, thereby letting you focus almost exclusively on unit tactics. At any rate, you're unlikely to see all the epochs in a single battle because an aggressive computer opponent will do its worst to write you out of history at the earliest opportunity. At the standard or hard difficulty settings, the computer will quickly expand across the map and will hit you hard and with just about everything it's got. Like most everything else about Empire Earth, the AI is no joke.
Perhaps the designers intended to make a scathing critique on how little humankind has evolved over the years, but the various epochs in Empire Earth actually aren't all that different once you get past the obvious graphical distinctions. Throughout all 500,000 years of history, you'll still need to gather food, wood, gold, stone, and iron. You'll do this by assigning peasants--called civilians here--to walk up to these resource deposits and scoop them up, exactly like in Age of Kings. Those same pumpkin patches feeding your cavemen will be feeding your modern-day military men millennia later--you'll have stealth bombers, but you won't have supermarkets. That same clump of gold will fuel your entire war machine throughout history. Similar quantities of resources will be used to train or construct historically analogous units. In the year 2200, you still won't have any technology that can cut through the fog of war.