Assasins Creed -

Driven by the creed "Nothing is true, everything is permitted," they fight for absolute individual freedom and free will.

The two groups represent diametrically opposed philosophies:

Formerly the Order of the Ancients, they believe humanity is inherently chaotic and seek to achieve peace through total control and order. The Sci-Fi Foundation: The Isu

Ezio Auditore da Firenze, perhaps the most famous Assassin, spends his life hunting the Borgias across Italy to protect the Creed.

Altaïr Ibn-La'Ahad reforms the Brotherhood into the organized form seen in later centuries.