The “Ninja Gaiden” series is respected and beloved across the entire gaming world and has sold 6.8 million units in total.In this collection the three titles from the series which are included are: NINJA GAIDEN Sigma (released in 2007) NINJA GAIDEN Sigma 2 (released in 2009) and NINJA GAIDEN 3: Razor’s Edge (released in 2012).Become the ultimate ninja and defeat deadly enemies!