Since the early 2000s, content filtering software (e.g., Securly, GoGuardian, Fortinet) has used URL blacklists, keyword blocking, and traffic inspection to prevent access to game portals like Miniclip, Cool Math Games, and later, Roblox or Krunker. Unblocked game sites emerged by:

Gamer Unblocked [patched] — Lost

Since the early 2000s, content filtering software (e.g., Securly, GoGuardian, Fortinet) has used URL blacklists, keyword blocking, and traffic inspection to prevent access to game portals like Miniclip, Cool Math Games, and later, Roblox or Krunker. Unblocked game sites emerged by: