It sounds like a forgotten Cold War bioweapon. Or a rare, furred rodent from the permafrost. Or maybe a lost children’s cartoon from the 1980s.

The best way to kill a ghost story is to stop feeding it attention. Have you encountered other strange "lost" internet keywords? Or do you want to know more about real Siberian wildlife? Let me know in the comments—but let’s keep the discussion clean, curious, and legal.

If you ever encounter any reference or link to "Siberian Mouse" that appears to contain real files, to your local cyber tip line (in the US, that’s the NCMEC’s CyberTipline).