INES Mapper 025

iNES Mapper 025 is used to represent the VRC4b and VRC4d variants of the Konami VRC4 mapper.

 Here are Disch's original notes:
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 =  Mapper 025          =
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 Mapper 025 is a variant of VRC4, which is covered in another doc.
 
 For info, see mapper 021.