Some single player games, such as Call of Duty or Battlefield, don't have much to do other than the main missions. They may have a few collectibles and extra trophies or achievements to collect but, by and large, once you've done the missions, that's it. Other games, such as Skyrim and Mass Effect, have tons of side missions to do. These aren't mandatory and sometimes the rewards aren't huge but they are still there.
Personally I don't usually do them. In Skyrim I did the Companions and Dark Brotherhood, and some of the Thieves Guild but that was it. The side missions weren't bad there just wasn't enough incentive to distract from a) the main story and b) just roaming around not really doing anything.
The same goes for Mass Effect, in the first two games I did some side missions but in the third I only did one, for me there is no incentive. That's why I like single player games to have multiplayer, I get things out of multiplayer that I don't out of extra missions in single player.
How do you play games? Do you do all of the extra missions? Are you a completionist? Or do you ignore most of them like me?
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