Free play:
Successfully complete the game with an "A" rank. Enter the options
screen and select "House Of The Dead 3". You can now increase the
credits past nine until "Free Play" appears.
Alternately, play well and get better than an "A" rank one or more
times during the game at the point where you lose all your credits.
This works best in one player mode.
Extra items in original mode:
Successfully complete House Of The Dead 3 then go to House Of The Dead 2,
You will take an elevator down to House of The Dead 2. On the way down,
the door will open a couple of times. Shoot all the enemies as quickly
and as accurately as possible to get items for original mode in
House Of The Dead 2. Complete House Of The Dead 3 again to repeat
the process. Every time you do this, you will get new items for original mode.
This works best if you unlocked the free play option for House Of The Dead 3.
Alternately, reset the game and when the title screen appears, go to main menu
and select The House Of The Dead 2. It will take you to the elevator.
Note: If you did not save the game before resetting, all the items you unlocked
on the elevator from the last time will be lost.
House Of The Dead 2:
Successfully complete survival mode in House Of The Dead 3 to unlock
House Of The Dead 2.
Sites: