I will add that a marvelous thing in all of From's games is that there is essentially no filler content. Every enemy (encounter) you meet is different in some way from every other, it's always challenging you in a slightly different way. There may be reused ideas between the games, but within a single game, you're never on clear a path of just doing more of the same. This is something almost no other company even seems to be trying, while From is constantly succeeding at it.