The Cypher System Rulebook is a 416-page core rulebook that contains the entire Cypher System rules (along with dozens of optional and genre-specific rules) and hundreds of character options, creatures, cyphers, and other resources. It's everything you need to run virtually any campaign using the Cypher System rules.
As a Numenera fan, you'll find new descriptors, foci, types, creatures, cyphers, and artifacts you can use in your campaign the minute you crack open the book. Many of the optional genre rules will benefit your campaign as well. There are pages and pages of content you can make use of in your existing game, even if you never take the Cypher System into another genre!
A Cypher System campaign of Victorian horror? High fantasy? Espionage? Galaxy-spanning space opera? Now, any of those will be as easy as running Numenera or The Strange.