Siostra is a guild that originated from the ashes of the mushroom guild. The mushroom guild was a guild that was lead by king Barfer. Barfer was determined to conquer godville, but on the way there the mushroom guild was ambushed by zombies along a forest path. The zombies added the mushroom to thier pack by converting them into corpse, and set off to conquer godville. Unfortunately, on the way there a flightless eagle came and well, they drowned in a puddle. A few zombies were able to swim an escaped, forming a new guild lead by the undead corpse of dead barfer. It is rumored that before you reach "master" you must be reborn as a zombie. this is the main reason Siostra remains a small guild.
to join siostra, your hero must pass the following tests, created by Barfer himself... (and some members)
1) build snowman under the ocean 9) meet chuck norris 2) eat out of a super bowl 10) dig a hole to china 3) donate 5 euro to charity 11) add a new requierment 4) opt to join the godville navy 5) know the abcs 6) destroy the first airbender 7) forget your name 4 times 8) go to jail