Mage: The Ascension 20th Anniversary Edition is a revised core rulebook for the Classic World of Darkness setting. Like it's Vampire and Werwolf counterparts it was released to celebrate the 20th Anniversary of the first core rule book for Mage: The Ascension. Though per se only a revised compendium of Mage: The Ascension Revised Edition and related rule books, it features not only updates to the modern times, but also more rules on things you could want to do and clearer recommendations to handle all kinds of situations.