back in the day I played a fun game called Empire over telnet.
It was a multiplayer strategy game where each player ran a nation that would acquire and build up provinces, setup your economy. you'd build a variety of units, give them orders to cover various areas for combat. this was way back when so there was far less automation of things. managing the logistics of your empire was a major factor, as lack of local resources could severely hamper your war effort in any theater, and the combat system was fairly detailed.
it was one of those games you could really pour hours a day into (at least during warfare and it was one of those games that lasted months).


Trying to think of some other old games that I quite liked, but that aren't so obvious that most people (who lived through the era and played games) would probably have heard of.
Maybe Onslaught? an old side-scroller I played on the Amiga with a variety of findable weapons that you'd use to try to conquer territories.