I have about 600 hours in this on steam and just bought it again on GOG........ its that good I need two copies Openworld sandbox, simple to learn (with help from the wiki anyway) yet surprisingly in depth and challenging..... Also you can farm fish for gold using a crab powered engine
This is a better game than people give it credit for, with a good solid single player story and fun gun play.... On the downside the game is only nominally related to the first red faction and it feels like there's less freedom with the destructible environment..... no more digging tunnels with rocket launchers However treat it as a game in its own right and you won't regret your purchase