This or Total Annihilation: Kingdoms?

Well, to clarify a few things:

1) TA: Kingdoms is a spin-off of TA. The original TA is futuristic, while Kingdoms, using the same engine, went the medieval fantasy route.

2) Supreme Commander is the spiritual successor to TA. And isn't really that old, so it's kind of weird putting it as an option when you're looking for an 'old RTS'.

Anyway, between those two choices, I'd go with Supreme Commander, if only because you'll probably get it to run easier than TA: Kingdoms(a DOS game) and it was pretty good. And if you consider SupCom old, then Kingdoms will probably feel too old for you. Not to mention Kingdoms isn't that great to begin with.

If you go with SupCom, I'd recommend grabbing Forged Alliance too. It's a stand-alone expansion that improves the game in a lot of ways.

If you still want an actual old RTS, then just play the original TA with mods instead. Honestly, TA is probably still my most favourite RTS. I remember having more fun with that back in the day than I did when I played SupCom or almost any other RTS.
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"Because I realize I want you. Guts."
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