The interface is pretty straightforward: the city is divided into 64 sectors under the control of one of the players. Each gang you hire is a unit on the map. Gangs can bring sectors under your control, and each sector has three buildings that can be brought under your influence for additional cash and bonuses.
Your main source of influence is "Chaos" - drugs, prostitution, racketeering, extortion, all the old standbys. The amount of chaos in your sectors has to be managed to not exceed a certain threshold, or you will become subject to the extremely lethal attentions of the police.
As you expand your criminal empire, its borders will soon bump up against the territories of other players, at which point you'll want some heavily armed and lethal gangs to take out the competition.
A nice range of additional equipment can be researched, from simple things like cool shades to hulking powered armor.
Chaos Overlords is an old game by now, and doesn't entirely hold up when it comes to graphics or user interface. A sequel was planned at some point but is now on extended hiatus, so who knows what will happen. A sequel is in the works! It's a fun game to return to every once in a while, for the zany gangs if nothing else.
Oh, and it's a huge if indirect inspiration for one of my future game projects. You'll see.