Warhammer 40,000 4th Edition Rulebook is the 4th core rulebook, published in August 2004. This is the limited edition hardcover with slipcase copy and includes the Limited Edition certificate.
This edition of the rulesset has relatively few differences to its predecessor so almost all codexes and supplements produced for the Warhammer 40,000 3rd Edition Rulebook are compatible. The lore sections took a much more objective look at the background of the 40k universe, yet still remained largely focused on the Imperium of Man's perspective.
The cover depicts a skull across a hammer against a dark abstract background illustrated by Karl and Stefan Kopinski. This cover is notable for the having the roman numeral 'IV' emblazoned on the skull, making this the only edition released thus far that includes the edition's number somewhere on the book.
In the nightmare future of the 41st millennium. Mankind teeters upon the brink of extinction. The galaxy-spanning Imperium of Man is beset on all sides by ravening aliens, and threatened from within by malevolent creatures and heretic rebels. Only the strength of the Immortal Emperor of Terra stands between Humanity and its annihilation. Dedicated to His service are the countless warriors, agents and myriad servants of the Imperium. Foremost amongst them stand the Space Marines, mentally and physically engineered to be the supreme fighting force, the ultimate protectors of Mankind.
Wars rage over airless moons, in the dark, twisted depths of hive worlds and in the cold wastes between stars. From the immaterial realm of warp space, malicious entities send their unspeakable minions to slaughter the Emperor's chosen. Everywhere, soulless spectres and slavering monsters are poised to extinguish the life of Humanity.
Rules Section (pgs 2-91)
What is a Wargame?
Unit Type Rules
Universal Special Rules
Organising a Battle
Background Section (pgs. 92-167)
The Imperium of Man
The Xenos Threat
Hobby Section (pgs. 168-263)
Collecting an Army
The Gaming Hobby