Is there a strategy game...

[SnakThree]

... that is large scale (so large maps, many units --> not like Company of Heroes) and allows for legit strategies / tactics, such as large flanking maneuvers and stuff like that, instead of just zerg rushes and rock-paper-scissor sort of stuff?

Vague, I know.

I've been searching the internet for a bit now, and all I found was the Total War series, of which I already have Medieval 2 (which isn't that great).

Medieval 2 sucks. I never forced myself to play for more than few dozens of turns.

Rome Total War if you are low on hardware. This one is pearl. I played through one full conquest. Few medium sized. I love it.
Shogun 2 if you are on at least medium. So many new features in comparison to RTW or M2TW. But this one is great game. Better diplomacy, map usage, unit simplification.

Though Strategy is very wide genre.
Do you prefer RTS ( Supreme Commander, Age of Empires ) or Turn Based Strategy ( Civilization 3 )? Both genres are combined in Total War series, which is obviously the leader of Strategy games in genera.

Civilization 3 is great game on very low hardware. It's Turn Based Strategy, no RTS. Has random map generator, which can leave you playing forever and ever.

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