It's difficult to say what caused a game revolution, as there have been a lot of games over the many years. But here are a few games that caused Revolutions in a big way.
Simcity - This game was amazing in it's time, being able to completely build up a city and control almost everything was fantastic.
Magic Carpet - I am not even sure what genre this is, but man it was amazing, and the graphics at the time breath taking.
7th Guest - 11th Hour and the Tex Murphy games - These were interactive Cinema games, not Farenheit or Heavy Rain, most of the concepts found in the two newer games were born in these early CD Rom games.
Dragons Lair - Spent many rands playing this silly quick time event game, but at the time it was like playing a cartoon.
Test Drive - Taking an expensive car of your choice out on to the road and driving it, brilliant. Number 3 even had a radio to play different radio stations.
Stunts - Building your own track and racing around it with the AI brilliant, only Trackmania seems to allow building tracks like this game did.
Mortal Kombat - Took 2D fighting games in a whole new direction, there were many clones, most forgotten but Mortal Kombat is still remembered.
Virtua Fighter - Yes Tekken is properly prettier but it wasn't the first 3D fighting game, at the time I thought polygons were a stupid idea to make a game out of.
Grand Theft Auto - Top down massacre had never been this fun, was lucky PnP at the time for some reason had this game in their bargain bin, picked it up for like R99 and got Fade to Black with it.
Dune II - Yes this was the second RTS out, but no one remembers the first and this became the grand daddy of the RTSes, I remember the first time I managed to get enough EMM to actually get speech in the introes.
Wing Commander - There is a lot that can be said of it, it's a mystery why this genre died down.