The rulebook PDF was included alongside a comic and the score with your copy of 2077. At least, it was at launch, maybe someone can confirm that it still is.
The 2020 tabletop game is a bit old, and of you get into the many splat books they published, a bit bloated. But it the rulebook alone is enough to have your own 2020 cyberpunk adventures, and has some lore and background as well!
Keep in mind, this is 57 years prior to 2077, but the settings aren't all that different. The world was set back hard by the Fourth Corporate war, so the 20s level of tech isn't that far in the 77 rearview. There's no quick hacking, but anything else in the game was there in the 20s!
Hope you find this usef
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