10 Video Games That Secretly Get Harder Without You Realising

While New Vegas retains Fallout 3's karma system, it's made rather redundant by the way more dynamic Reputation system, where your actions affect how you're viewed by members of various communities throughout the wasteland. And this system can really screw you over if you're not careful.

When you first meet the Legion in Nipton, having just wrapped up their magical murder tour of the city, your first instinct might very well be to keep the party going. This is especially tempting if you're starting with all the DLC installed, and thus have a handy grenade launcher to really clean house before they know what hit them.

However, get ready to have a bad time going forward, because this is when the reputation system comes into play.

See, now the Legion knows about you; knows that they have a psychotic mailman with a grenade launcher wandering around shooting at them. And they will respond in kind. Which would be fine, if you were in any way levelled and equipped enough to handle them, which you most likely are not.

So if you'd rather not be in constant danger of being jumped by random heavily armed cosplayers, best to just let Vulpes and his posse go on their merry way.