The Warhammer 2nd edition core rulebook provided only a fairly barebones version of sorcery rules, like it did for religious “spells” and many other subjects. This is not a put-down on the main corebook, it’s just an acknowledgement of space constraints. Realms of Sorcery aims to fix that… and to a large degree, succeeds.
The book aims to provide Warhammer magic with flavor and character, not just some “burn mana and get a fireball” system. To this end, magic is separated into different “winds” (or colors), shades of an underlying magical force which different people are sensitive to, in different degrees. Theoretically, one could manipulate several magical “colors” at once, but Humans find that extremely difficult, so generally one “mage” focuses on one type of magic. Spells take great concentration to cast, and failures can be very bad due to the close relationship of magic and the forces of Chaos.
Where the book shines is the back story behind the Magical Colleges of the Empire, and the Colleges themselves. Each color/type of magic shapes the mage, and therefore also shapes the magical organizations, the Colleges. They are all quite different, with varying focuses, ways of taking in and teaching students, and political interests. Naturally enough, the book also provides a huge spell list, much expanded from the one in the core book. For anyone looking to play a sorcerer in Warhammer, this book provides them with most of what they need. It also provides GMS with lots of background information and color on the Colleges and magical society in general – including the illegal forms like witches, warlocks and other probable Chaos-worshipers.
I say “most of” above, since the book leaves out some things. There is little information on rituals, even though those feature in quite a few Warhammer scenarios. Also, there is no real information on low-level spells, what would be “cantrips” in other systems. One assumes stuff like that exists, and the flavor text hints in that direction, but the actual rules support for that isn’t to be found here.
Those faults are fairly minor in my view, seeing as the book as a lot of information and make magic use in Warhammer both interesting and potentially explosive. It’s very different from the flavorless and safe magic in D&D variants; here, using magic makes you shunned (if not actively hated) in society, and runs high risk of making you insane, inviting demonic possession, or just plain blowing you and your companions to bits. Safe, it really isn’t. And that’s good, I feel that “safe” magic is usually also boring magic.