Rent A Hero No. 1 Cheat Codes for Dreamcast

Hidden artwork
Place the game disc in a PC compatible CD-ROM drive to find images from the game in .BMP format.

VMU mini-games
Go to the following locations to unlock hidden mini-games on the VMU.

Look in the box with monster costume in mother and father's room.
Search the arcade machine in the back of the arcade in Ohtory.