Metal Slug 7 marks a handful of firsts for the 12-year-old 2D action series: It’s the first Metal Slug without an arcade release, and the first on the DS. But don’t expect a stylus-driven touch-screen-based reboot of the franchise at al.From what we’ve played, this is a traditional Metal Slug experience through and through: gore-tastic 2D graphics, giant screen-filling bosses and plenty of things that go boom.