In reality, these cartridges typically only contained between . The "999,999" count was achieved through several tricks:
A typical "99999-in-1" ROM does not contain 99,999 unique games. The actual NES library only consists of about 716 licensed titles in North America and around 1,050 in Japan .
If you choose to use torrents, always use a no-logs VPN and do not seed copyrighted material. Better yet, use direct downloads from archive.org (check legal status in your country).
This article dives deep into the phenomenon of massive NES ROM packs, the truth behind the astronomical numbers, the legal landscape, and how to approach the "top" downloads safely.