Finish the game second time.
Go beside the enemis as near as possible. Do not go to the front or the back because torpedos at front mines at back. You will find it easy to target.
Finish the game and play the new game. You have to save the game first.
Finish the game and unlock it.
At the final stage part 8 15 fight, get your free torpedo at the torpedo shop. Because you don't have to pay it. So take as much as you can and sunk the enemis down.
At part 3, 7 fight (save the game and talk to after that she will give you 10,000 steels then you save the game.) If you want more just repeat (save the game......).
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