Great Wolf Logan Grimnar leads his Wolf Guard into battle.

Since the Imperium came into being, the Space Wolves have fought tooth and nail for the cause of the Emperor. Among the most famous of the Chapters of the Adeptus Astartes, their name and actions are known from one side of the galaxy to the other. As headstrong as they are fierce, the Space Wolves are experts at close-quarter fighting, and their warriors compete keenly for glory on the battlefield. The Space Wolves live to fight, and death holds no fear for them.

Perhaps as a byproduct of their unbridled ferocity, the Space Wolves tend to ignore the orthodoxy laid down in the Codex Astartes. Their Chapter is organized into Packs, not Squads; Great Companies led by Wolf Lords, not standard companies. Their armour is adorned with runes and wolf emblems contrary to the standard Space Marine garb.

Many young Space Wolves start out as Blood Claws, a pack devoted to hand-to-hand combat. When they have proven themselves in battle, they move on to the Grey Hunter packs, skilled in both long-ranged and short-ranged combat. Contrary to other Chapters, next are the Wolf Scouts, made of experienced warriors used to operate far behind enemy lines. If they live long enough, Space Wolf veterans become Long Fangs, providing heavy weapon support. Lastly, the Wolf Guard is comprised of the best warriors available, protecting the Wolf Lord.

Two other things set the Wolves apart from other Space Marines: their access to the Imperial Guard Leman Russ Exterminator battle tank, and their use of Rune Priests, Wolf Priests, and Iron Priests.

Lastly, the Space Wolves have two standing Blood Feuds. First, they despise the Thousand Sons Chaos Space Marines for their treachery during the Horus Heresy. Second, they hold a grudge against the Dark Angels over a spat between their Primarchs thousands of years ago.