Factions aren’t really being established here. Guilds differ from factions in that guilds aren’t at their core pvp driven, rather they are community driven. I’ve seen the Mc faction servers before, so I think I understand your concern with factions. A guild can do lots of things besides pvp, and their allegiance can go what ever way it’s community wants, unlike factions.
All the game really needs for a guild function to be successful is a way to mark a player as a member, guild hierarchy and a guild communication channel, whether that be a private chat or message board. Guilds could take on any profession from mason guild to adventurers guild, even class based guilds like mage guild or theives guild.
All a guild really does is allow like minded players to form their own private community.
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