The Sega Master System and the Sega Mark III are basically regional variants of the very same console...
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Sega SaturnSega Game GearSega DreamcastSega Mega DriveSega Master SystemVMU
Sega Dreamcast Visual Memory UnitSega CDSega Mega Drive 2GenesisSega Mark IIITerra DriveSuper 32XMega CD2Robo Pitcher?And "Sega Hard Girls" are?