Before we get into this, know that this is a HUGE book! It's crazy-huge. It can cause structural damage when dropped (I assume, since I haven't actually SEEN the physical version, but best not to risk it I think). It is ALSO brilliant for all sorts of reasons.
Mage: the Ascension came out at a time when magic (or 'magick' as we say in the biz) seemed to be failing as a concept. Sure, we had D&D and some stuff from Star Wars or what-have-you. The thing is that Mage brought magick to OUR world, or to the World of Darkness as it is within the game. More than that, though, this form of 'magic' felt real, with requirements and societies and responsibilities – not to mention a LOT of rules – in a way that made it more wondrous, scarier, and ultimately just mad-compelling in a world that didn't know how truly miraculous its very existence is.
...Then came the other editions of Mage. I won't say that any one of them was better or worse than the rest (however, know that I DO have my own preferences), and even with the various improvements and tweaks, changes always brought controversy. After the third – excuse me, REVISED – Edition, old White Wolf packed it in for the World of Darkness, bringing us the Reckoning that finished their game lines and allowed for the 'new' World of Darkness to come along. So all of the worlds ended, and end of Mage came with a bunch of unresolved feelings for me. I wanted more of the lore, more of the Otherworlds, more of the magick that I found in Mage: the Ascension. I didn't want it to end...
It turns out that it never did end, not really, and in true fashion of what I loved at first sight in Mage, this book is a little (irony intended) piece of magick in its own right.
This book, 'Mage 20' or just M20 to some of us, is labelled and presented along the same lines as Vampire: the Masquerade Twentieth Anniversary Edition (or V20 in our 'gamer' shorthand), but this is NOT the same kind of book. The V20 is a dolled-up compilation with some 'spit-shine' on rules and new art. It's lovely, no doubt, but from the outset, the Developer Satyros Phil Brucato (his real name... now) wanted to do more with M20 than simply compile two decades of Mage titles into a single volume. What he and his team did is nothing short of a physical and notional manifestation of the same willworking that Mage planted into my mind so long ago. It's all that came before BUT nothing like its predecessors. It remembers the past (even those what may not have ever happened!) WHILE keeping an eye locked on the future (even those futures that may never come about... Trust me, it's a magick thing that makes sense in the game). It gives you everything that you need to play just about any form of Mage: the Ascension, and YET it straight up TELLS you that nothing presented needs to limit your experience.
All of the factions are here, updated and shiny. All of the Spheres (including those of the Technocracy and their ilk) are here with crisp and clear presentation. All of the histories – up to and beyond the Avatar Storm of Revised Edition – are here. So too are polished mechanics for travel outside of our mortal realms, for magick casting, for wonders and bygones and more. Also here is advice to players and Storytellers for Mage games, along with so many charts and tools that you'll feel like you ought to have paid tuition along with the purchase price (that's a joke... but just). Oh, and don't forget the fiction, the art, and the gorgeous presentation. It's not just magickal, it's a work of art made of love, ink, and paper!
Speaking of paper (or virtual pages, such as the case may be), it is HUGE. I mentioned that before, but it bears repeating. You don't likely need all nine Traditions, all five Conventions, all ten Disparate Sects, but it's wonderful that they're all there. Your game may not include the Otherworlds – or it may only include SOME of them – but it's all there. The nine Spheres (the mechanics of how magick works if you don't know) maybe don't need the three 'technomagick' variants, but those add plenty to the game. It's daunting, as mentioned by other reviews, but that's the nature of magick, I reckon. If you want to explore this world – or get reacquainted if you already know Mage – this is a great product for you.