Dragon Quest Heroes: Rocket Slime Cheats (Nintendo DS)

Go to the church and enter Y, R, R, up, L, L, Y, DOWN, DOWN, DOWN, Y, SELECT.

After you get all of the 100 slimes and defeat the final boss (Flucifer) go to Mt.
Krakatroda's east tank arena. Instead of the usual boss it should be Slival. 

Fight him and win (his tank starts with 3000 HP). If you do win you will be rewarded with
orchalslime and access to the Swarzman tank in Morrie Morrie's tank masters tournament.
You can only access the tournament by getting 55 slimes or more and Morrie Morrie. He can
be rescued from a tank battle).

Go to the church and enter Y, L, L, Y, R, R, Y, UP, DOWN, SELECT.

Go inside the church and press Y, L(2), Y, R(2), Y, Up, Down, Select to unlock the helmet
slime tank in Challenge mode.

Go inside the church and press Y, R(2), Up, L(2), L, Y, Down(3), Y, Select to unlock the
female slime tank in Challenge mode.

Finish the game. Then, talk to Meggan in the northwest building.