The Moon Warriors guild was a guild that helped against PKs, but unlike the "white" guilds of Tibia, they only interfered when asked, rather than running to defend every player under attack. Their theme was the below:
"... and it happened when we were yelping with the wolves one night. It was a full moon that lit up the night. And we decided to pay homage to the moon, the light of the night. When we were done with the whine we sacrificed our light and so the guild of the Moon Warriors was born!"
The guild focused on showing respect to other members, obeying the consuls (guild leaders), trading with other members at a cheaper rate than others, and killing only in an emergency or with prior agreement. From their codex it was clear they wanted to avoid trouble as much as possible and stay out of conflict with other guilds and players. This guild existed in Beta 4 but it doesn't appear that they remained a guild for very long. _octopus and Scheijan may have been the founders of the guild. Though they had two websites, only the first exists in a much reduced form