Welcome to our community, Ships_of_doom!
Like you, I was a jack-of-all-trades gamer who have played tons of different games, especially demo ones. I played TA:Kingdoms back in 1999 when I bought a CD with dozens of demos; one of those demos was TA:Kingdoms Demo. I was actually amazed by the game aesthetics, like its variated and detailed backround of the map, its destroyable/flamable/cleanable trees and rocks, its physics engine where obstacles block your arrows and higher elevation grants you greater line of sight as well as longer weapon range. The animations of the units were awesome; I still remember staring at my Mage Builder's flag waving at random, being pushed by the ever-changing wind, my archer drawing his arrow to load and fire his bow, my Troll raising his great axe and striking the hostile Warrior...
The four kingdoms were all available in the demo skirmish version, though only tier 1 units & structures were allowed (and some tier 2 units for Zhon), letting you messing around with all the four Monarches of Darien. I still remember the awesomeness of their attacks; a regular slow attack that consumed no personal mana, a faster and more powerful second attack which requested a fair amount of mana to be wasted, and a third wave attack capapble of destroying any masses of lesser troops, full-draining your personal mana supply in the process.
The 4 demo missions were also awesome! In the 2st mission, you could either wipe out your Aramon enemies by rushing with Lokken or taking your time and build your forces for a large-scale battle. The second one was a Zhonian mission where Thirsa had to conjure forces and wipe out the Aramon/Veruna forces. Back then, I didn't knew the Shift + click or Ctrl + click tricks for queing and training a lot of Zhon units one after the other, so I had to micromanage my Handlers a lot in order to win. I was also amazed by the Verunan Skiffs and Transport Ships at the aquatic area of that map; they were pretty detailed models for an 1999 RTS and they were shaken if hit by the 2nd attack of my Thirsa! Furthermore, they left a really amazing wreckage behind, slowly descending to the depths of the sea...
Hurray! The 3rd mission was a Veruna one and gave you controll of those ships you fought before, as well as introducing 2 brand new ship models; the Harpoon Ship and the Man-o-War! The Harpoon was an amazing row-moving ship with a powerful harpoon attached on it. The Man-o-War was an even more amazing cannon ship, where its cannons even turned a little in order to hit their targets more effectively! Like this wasn't enough, I discovered that every single kind of ship could transport a fair number fo troops, with Skiff being able to transport 1-4 soldiers and the Transport Ship more than 20. In other RTSes, you could transport your armies by using Transport Ships only while the other kind of ships were only for war, which was kind of lame compared with TAK. Since you hadn't any Sea Fort, you couldn't build any more ships and you had to take care of them while using them to unload your Veruna army and retake the east shore from the Tarosian forces.
Finally, the 4th and last mission of the demo version put you as the commander of Aramon, controlling Elsin and using him to fortify the castle around, building Walls & Watch Towers and training soldiers from your Barracks. Zhon was your enemy, attacking you from 2 different sides. The highlight of that map was the Ancient Dragon who attacks your base in that mission and I have to say I watched in awe as he destroyed a fair amount of my defences before being taken down by my Elsin. The dragon model was surprisingly detailed with perfect flying animations and 2 different ways of attacking!
However, the most impressive part of the game was its resource gathering system. One resource (mana) is gathered by building a Lodestone on the Sacred Stone. Plain and simple, this resource system allows you to focus on combat and defense building instead of messing with 4-5 different resources and economics. Despite of being a highly criticized system at its time, it inspired Warhammer: DoW and Comany of Heores resource systems, making TA:Kingdoms the 'mother' of point-controll resource gathering system in RTSes.
I bought the full version of TA:Kingdoms when the Greek version of Computer Games Magazine had put TA:K as a free full game along with their magazine in 2005, if I remember correcly. I was actually amazed even more by the full version, since the fractions were even more different, with tons of different units, tons of different maps and a Cartographer which allowed you to create even more of them (like they weren't enough!). Furthermore, it must be the most easy-to-use map editor in the world, since you edit the tearrain via tilesets and not sqaure-by-square like other RTSes of that era. Let alone the epic documentary-style cutscenes, super soundtrack and tremendous story of the Book of Darien campaing! Moreover, it was probably the first rts that forced you to change races as the campaing's story was procceeding.
I discovered the community when I lost the CD. I thought I could find the game somewhere on the internet, in 2010, and I found kingdoms.heavenforum.com! I downloaded the UTAK pack and finally was able to play the expansion pack that added Creon as the 5th race and a whole new Iron Plague campaign! Though much more difficult than the Book of Darien, I've managed to finish the Iron Plague, mostly motivated by its magnificent story, but also because I wanted to join online TAK gameplay and finishing IP would help into filling the gap between me and online TAK veterans. After finishing most of IP, except mission 10: War Toys (God, I've never spent so much time on any other mission on any other game, ever!), and defeating 7 AI opponents allied against me on various skirmish maps, I decided I know everything of single-player TAK and its time to play multi-player TAK too!
Though my complete single-player experience, I was easily wiped out by TAK veterans in less than 5 mins, making the AI looking like a complete noob in front of them. But online TAK is so awesome that I don't care. I lose almost every time in 1v1 (though 2v2,3v3 and 4v4 are much more incredible, mixing units & tactics from every single kingdom) and we sometimes lag a lot(crappy internet connections combined with crappy routers and people playing from all around the world with a tornado in the middle of Atlantic ocean can lead to a very laggy mixture), but we have such a great high-quality amount of fun it doesn't really matter!
But the fan doesn't stop with the original TAK. There are dozens of new races, maps and mods that have been created and released, adding even more to the overall experience. Reently, we also brought back to light an underestimated and underused feature of the game; multiplayer missions made by the Cartographer! Ranging from Tower Defense to assault-like and from Co-op to PvP, multiplayer missions came to stay for sure! Finally, thanks to Rammstein, a single-player-mission mod has been made, allowing you to run multiplayer missions like singleplayer ones, eventually making single-player missions possible...
Long live TAK!