Assertion: doom's level | /r/HasProperty | played by estimated 15–20 million people
Facets:
value: within two years of its release
type: TEMPORAL
value: with one third of the game
type: OTHER
Source sentences:
text: With one third of the game, nine levels, distributed as shareware, Doom was played by an estimated 15–20 million people within two years of its release, popularizing the mode of gameplay and spawning a gaming subculture.