46 12 25 is the soundtrack code in Sonic CD which triggers the anti-piracy screen.

There, you can see this strange redesign of Sonic, plastered everywhere on the screen. The Boss!! theme from the American release of the game will begin to play in the background, and a message written in Katakana shows up bold white across the screen.

The 46 12 25 screen can also be caused by the SEGA CD system reading it as a pirated copy.
Person 1: Hey, has anyone tried typing in 46 12 25 in the soundtrack menu?

Person 2: Don't try it. You will more likely than not mentally scar yourself.
by GameSecrets June 25, 2017
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