Chronicles of Amber.

This volume collects all ten novels tracing the adventures of Prince Corwin and his son Merlin, as they discover what forces are attempting to destroy them, and in the process, save the fabric of reality itself.
1. Nine Princes in Amber 2. The Guns of Avalon 3. Sign of the Unicorn 4. The Hand of Oberon 5. The Courts of Chaos 6. Trumps of Doom 7. Blood of Amber 8. Sign of Chaos 9. Knight of Shadows 10. Prince of Chaos

Not all editions listed on this page are for the same book, for example the 1978 and 1972 editions are limited volumes. The 1978 edition includes only Sign of the Unicorn, The Hand of Oberon and The Courts of Chaos, the 1972 edition includes Nine Princes in Amber and The Guns of Avalon.