Dominions 3.
This is an indy game made by a two man team. It is feckin awesome. thousands of units, thoudands of spells thousands of items, thousands of combos and strategies. Multiplayer is one of the deepest richest fun experiences you can have on a PC.
Graphics are circa 1995 but if you can get past this the game engine and playability out shine other TBS games hands down.Gal Civ 2 for example can not hold a candle to this.
Dom 3