A Relic Blade is a large Power Weapon often resembling a sword or axe surrounded by an power field for shearing through armour. Due to their size and weight these weapons must be wielded two-handed, but are of immense importance to the Space Marines who carry them. Many have their origins in the dark days of the Horus Heresy, while others were created many centuries later as tribute to other momentous events.
Only after a Space Marine has proven himself may they be given the right to carry a Relic Blade into battle. Among these are Space Marine Honour Guards, as well as certain Vanguard Veterans and Captains. Perhaps the most famous example of a Relic Blade is The Spear of Vulkan, currently carried by Vulkan He'stan of the Salamanders.