Space Wolves

Space Wolves [Space Marines] are renowned for their ferocity in close combat, and any unit with the Space Wolves ability adds +1 to their Assault value after doubling for the Hero ability or halving for Heavy Weapons, not before.

This rule only applies to Space Wolves infantry and Bikes, Attack Bikes and Land Speeders. Space Wolves armoured vehicles, including Dreadnoughts, gain no additional benefit.