A very tough strategy shoot'em up game. Read in-game instructions and mission information. Good luck!
If the game seems to be too hard, try these things:
1. In options, turn "Old bullets" option on
2. Use Hand grenades (4) they can bounce when they hit a wall
3. Use Alt. attacks.
4. Cheat codes form EW1 still work! (press and hold YMP or ZLT or XHI to get SuperShotgun,Minigun or RocketLauncher)