Green Pixels' Christina Troup writes:
"It's unfortunate, but more times than not, the most marginal success – we're talking the cha-ching of sales, folks -- leads to a sequel. And, as we all well know, not all games are deserving of a follow-up. But, for every game that totally blows the second, third and sometimes even fourth time around, there are those gems that stand out and go above and beyond their predecessor. Here are six of those games."