Total Annihilation is the best RTS of any age, it was ahead of its time, and still beats out modern strategy games.
What will first strike you as unusual about Total Annihilation are the 3D graphics, combined with pre-rendered 3D terrain (which became the norm after its release) instead of pixelated hand drawn areas, it was most likely one of the most beautiful games of its time. Explosions were amazing, more than just tiny little bitmaps, instead, the entire nearby area would be lit up, and debris would fly in every direction. With a cast of fully mechanical units, it was a normal sight to behold around fifty tanks all exploding at once from a nuke streaming from the sky.
The story in Total Annihilation is filler at best, but it does nicely. A century long conflict between the Arm and Core, two different warring factions, continues as you assume command of their armies (whichever you choose) they've battled across countless planets, used limitless amounts of resources, and are still going at it. It's almost a battle between machines, as mechanical warriors have taken place of humans on the battlefield. The campaign is probably the least interesting aspect of Total Annihilation, but it's still well done, missions are varied, and there's a voice over for each one of them. There's a rather high amount of missions for both sides, and each has a few memorable moments that'll keep you reminiscing about just how completely insane or close it was.
There's a wide variety of actions in Total Annihilation. The AI is well constructed, and there are many useful orders you can carry out. Units can be set to roam, exploring the map, or just attacking random units, they can patrol, attack on site, wait until they're attacked, stand totally still, retreat upon site of an enemy, and more. There's a vast amount of these different orders, and they provide limitless strategies to the game. Placing a patrol over a contested pass between two mountains with a few of your airplanes could provide a nice barrier for enemy troops for example. While Total Annihilation has a rather overwhelming illusion of total chaos, it's never unmanageable, and despite the fact that there's around a thousand units all battling at different points on land, air, and water, you'll never lose track of what's happening, which is good, since action heats up quickly. Despite the rather traditional "unit massing" the game encourages, a clever player can easily destroy massive armies with the proper units and techniques, which totally throws off players who in other games would simply create a mass of the same units and throw them constantly at other players.
Unlike other strategy games, battles in Total Annihilation can be very tight packed or long range. Missiles can fly half-way across the map and certain pieces of artillery can deliver destruction from jaw-dropping distances. Whereas some units will get right in each other's face and begin blowing each other up with reckless abandon. This provides a great contrast, since it delivers multiple layers of complexity to what might otherwise be mindless insanity. A troop of short range Pee Wees, for example, might be able to massacre some long range slow unwieldy tanks, while some overhead mid-range fighter jets could easily destroy the weak but cheap Pee Wees. Instead of providing a different range of resources to harvest from different points on a map, Total Annihilation nearly completely removes the hassle of resource management by providing two solid resources, Metal and Energy. Energy can be created simply by building power structures, and Metal is obtained by building Metal Extractors on designated spots on each map. What's great about this method is that these buildings will give you an endless supply of each resource, and there's no limit to how much there is, a Metal Extractor you build five minutes into the game will still provide the same amount of metal an hour into the game. The same goes for energy. You can also recycle energy and metal, since enemies or friendlies that explode on the battlefield all leave debris (which vary from smoking husks of metal, to small little pieces of debris scattered around) you can easily harvest that for more metal and energy, or harvest trees, rocks, and other natural flora for energy. Most games in Total Annihilation center around your Commander unit, which on most games is your primary and most important unit (it's usually set that when the Commander dies, that team loses) he builds the fastest, he's one of the hardiest units in the game, his D-Gun is one of the most powerful weapons, and he can harvest nearly anything in the environment for resources, he can also build structures that no other unit can. Throughout your game, you will have to protect him, although with proper care he can be a lethal weapon (one shot of his D-Gun can turn a quarter of a base into smoking rubble). The sound is one of the highest points in Total Annihilation, not just for the fact that nearly everything has an appropriately massive sound (explosions deliver a definite boom, and etc.) but because of the incredible soundtrack. This orchestral masterpiece by Jeremy Soule is probably one of the greatest I've ever encountered in any video game. While the operatic sound may seem unsuitable for a game with Total Annihilation's carnage, it can't suit the game better than it already does. Hearing vibrant horns, violins, and the such over a raging battle will get your adrenaline pumping and elevate the game to an almost cinematic level. With its music, Total Annihilation can deliver some of the most entertaining to watch conflicts in any game, just because it draws out like a war movie. Brigades of slowly rumbling tanks moving over hills firing at fast but weak units emerging from the tree lines, setting an entire forest ablaze with fire is just breath-taking. Even now, the only games that can possibly even touch the level of detail into making these battles come to life can be titles such as Company of Heroes or Dawn of war.
If you haven't experienced Total Annihilation already, there's absolutely no reason not to. What is probably the greatest strategy game ever is waiting for you, and it won't dissapoint. If you're fighting around flaming lava, green forests, or a snowy planet, Total Annihilation will always deliver the carnage and scale you always wanted in an RTS.