Ninja Gaiden Sigma 2 is a long way from release time, set for October 1 in Japan.

While we're still waiting, Japanese media continues reporting new details for the upcoming Sigma sequel.  We learn via Famitsu magazine that Sigma 2 will have online co-op, separate from the main story.  This "Team Mission" mode will offer one-off missions to choose from and character options.  Each mission should be beatable in one go and includes an boss battle.

You can, of course, play through these missions solo with an A.I. ally, but we all know how well that usually works out.