TA Zero is a total conversion for TA with focus on smaller, micro-oriented battles (whilst still allowing the big scale). And since there is a streaming-resource system, you can queue up production, which enables you to actually do all this micromanagement, without being a god in this game. This makes it very appealing for occasional play.

The original Total Annihilation had some weaknesses (like in unit design or balance), but TA Zero is a completely new game in this matter. Due to the flaws and age of his antecessor TA Zero is way less popular as it should be.

This mod is in alpha-stage, but unit-design is completed enough to be played in skirmishes via LAN or GameRanger or against a well done AI, which is actually a challenge.

The unit-handling with the TA-engine feels really good. E.g. direction of units and acceleration matters. It actually makes a huge difference whether you direct your aircraft manually, so that enemy bombers are in coverage of your fighters weapons. Also, a moving army always recieves less damage since enemy shots will miss, so you should't just plan where to park your army, but also where and how to move it during confrontations. You don't find this in other RTS like SC2.
But the original TA was never able to match with games like SC with regard to competitive/online play. Now here comes TA Zero with a completely new design, taking the good aspects of the TA-engine and integrates them into gameplay which leads to faster matches with multitasking instead of unit-massing.

While the other big mods like Escalation added stuff to the original TA and made it more similar to Supreme Commander, TA Zero revised seemingly everything and brought it closer to StarCraft. (Just closer, it's not trying to be SC.)

Check out the Total Annihilation Zero Youtube channel by TaShadan to get an impression of the gameplay. :)

Check out my youtube channel for gameplay videos. https://www.youtube.com/channel/UCIGJ_Jt1C7W0MU5RHn2h10w
PS: Pathfinding is significantly increased in TA Zero.

"The unit-handling with the TA-engine feels really good."

Since this is so highly subjective I just want to give a short description of my taste:
I prefer the pathfinding in WC3 over SC2's. The way you handle your units in WC3 feels more natural to me. I experience them as actual individuals, blocking each other, having no perfect coordination.

If you want to get an army down a small ramp in WC3, you get the feeling that you really have to "push them through" the tight spot.
In SC2 they just flow down the ramp like water. Or marbles. It feels wrong to me. Also the box-selection-problem with hovering air units over your army feels so bad. (In TA adressed with W-key: whilst pressed you only select armed ground forces.)

Anyone, who likes the comfort of marble-units has of course totally different tast than me and will not appreciate old game-engines as I do.

I don't think that you'll like it then. It even focuses on the unit micro and de-emphasises the macro (-clicking) compared to SC.
The game is about "playing with your units". Fore the big scope there are games like Supreme Commander, which are to me like a different genre. Where you actually have the time to think about strategy ingame.
If you play StarCraft, you cannot plan strategy ingame. You just execute it, and planning happens between games.
It's more of a "multitasking-RTS", in contrast to the "planning focused-RTS" like SupCom. Even the original TA was for me in the latter category.

It's easier in TA to focus on unit-"babysitting", because of the mentioned resource system. On the other hand, I never considered the few buildings you place in WC3 problematic. Multitasking is a requirement for a multitasking game. :P
The handling of my stuff like it's partially an action game, is about the basic enjoyment of such games to me. The strategy makes it interesting in the long term.

If you are a not a casual player, but you only play occasionally (compared to people that want to become a pro), you like Blizzards RTS, but SC/SC2 requires too much routine concerning macro, this game is an interesting alternative.

Interesting comments.

I just remembered something about the expansion for TA 'battle tactics' and you know what, i have never actually played any of the missions under medium length, even after all these years!

I think that really tells how much unit hand holding is not interesting too me..... i just love the build side of the game and i do not like being dragged away from that to deal with silly little AI raids.... at least until I'm ready!

In view of above, it is fairly clear to me now why i could never enjoy a game of Warcraft3 or Starcraft even though they are such popular games.

Some other RTS i liked was Age of empires1 (but not 2 or 3), and i can play praetorians but it is not one of my favourite games. The one other RTS i really love as much as TA is Rise of Nations.

The common theme with RTS i do like is being able to use strategy to set up defensive positions which require less attention and the common theme with RTS i do not like are the ones designed to prevent you from using strategy to set up defensive positions because it is trying to make the game more challenging for players..... but in my case it just makes it bloody annoying.

Prevent defensive positions? What are you talking about? You actually never played games on a high level. At least Starcraft Broodwar and Total Annihilation Zero require to establish defenses at certain points, while attacking on other points.
You are quoting AoE1 and TA as a games you like? In fact AoE1 is a very fast game and does not benefit bunker people and TA is only about spamming flashes and samsongs in early game, bunkering will lose you the game as well. You should play turn based games with a mind set like yours. The Age of Wonders series is great or play Battle World Kronos. Battle for Wesnoth is great too and it is free.

Don't be too harsh on him. :) His mindset is perfectly okay. That's why I adressed this more to SC players (or even MOBA players) which have the mindset to search for challenge in games.

Against AI you can actually play the slow turtle style in Zero, without fast control. Then you just have a prettier version of the original TA with a better AI.

Holy cow this is wrong on so many levels I don't know where to start, actually it's not even worth to bother with the rest of this thread. Proper TA played by the best of the best ever is so unreachable for the vast majority of the folks that even koreans, when they do come, they get owned badly and never come back. Of course that has to do with the language as well but still...

If you think TA doesn't require multitasking then that just shows what incredible low mediocre level your real TA level ever was. I like TA:Zero, it keeps Arm and Core whilst adding a 3rd race, keeps many units and better of all the original units now have a difference appearance, which is very intuitive. But to say that small Cavedog's TA is below a game that you can't even customize your resolution is beyond silly.

TA is the best RTS of all time, son. It's in every unbiased/unpaid proper lists.


PS: the original pathfinding increase was in the OTA patch. Mods just copied it after that.