The Uprising mode converts every enemy you kill and every bonus you receive into points, which are used to buy power-ups for your character that change the play in a number of ways. More powerful weapons, more lives and continues, more abilitiesby playing the game and learning the levels you'll become more powerful over time, and the compulsion to see just how high you can score will keep you playing for a very long time. It's easier to take getting killed over and over when it gains you the points needed to buy that one new thing you've had your eye on for the past hour.
If you're saying to yourself that this sounds horrible, please do not take my final verdict to heart. Stay away. But if you feel challenged, and if you're in the mood for some punishing, old-school gameplay with wonderfully modern graphics, you're going to have a good time. You'll see nods to previous Contra titles, you'll explore a variety of locations and environments, and you'll likely throw your controller once or twice. The game is never cheap, not really, but it certainly has a few points where it goes out of its way to "get" you, and those moments can be infuriating.