I love shooting games and HOD II is the reason that I purchased a Dreamcast rather than waiting for the PSX 2.  HOD II continues on from the original as you are part of a team of government agents once again trying to stop a Zombie creating madman.  You shift from screen to screen, using the Sega Light Gun to blow away various bad guys as they charge at you.  Depending on how and who you shoot, the game branches off through various paths.