The Aetheromancer's Cogblade, or simply the Cogblade, is a an artifact of unknown origin in the Steampunk section of the D-Verse.
The Cogblade is best explained as a flat-bladed, two-handed sword. It measures 68" (five and two-thirds feet) from the end of the hilt to the tip of the blade, and consists of three sections: the hilt (11"), the crossguard (3"), and the blade itself (54").
The hilt of the Cogblade is an inch-and-a-half-diameter, fairly regular cylinder of dark gray (almost black); it is always slightly warm to the touch, regardless of the environment. The material itself is a curious blend of metal and stone that defies proper analysis, though most users have approximated the feel of its surface as something akin to extremely smooth-grained granite.
The crossguard of the Cogblade is, at a full three inches, much taller than might be expected for most functional blades of its size; it is also two inches thick and eight inches wide, a rectangular prism. Like the hilt, it appears as an extremely dark gray stone/metal with the same tactile properties.
The Cogblade takes its full name from the inscription on the crossguard, which is a much lighter gray than the rest of the hilt and reads as follows in half-inch-high Roman lettering.
PROPERTY OF THE AETHEROMANCER
As no other blade has been discovered with anything approaching both the Cogblade's design and its special properties, the meaning of the IV is still unexplained.
The main body of the Cogblade's blade section is a bright silver that contrasts sharply with the hilt and crossguard's dark gray, a uniform six inches wide and one inch thick until the last three inches where the blade comes to a point, also the only area of the entire Cogblade that is actually sharp. Tactilely, the blade is closer to metal, though with a surface texture invisible to the eye but quite apparent to the touch.
Three six-inch-diameter, half-inch-thick gears are set four inches into the blade, centered at nine, twenty-seven, and forty-five inches from the crossguard. With the crossguard inscription held facing up, the first and third gears are on the left side, the second gear on the right. The gears are apparently identical; each one is straight-cut with teeth no more than a quarter-inch wide. Unlike the blade, the gears are smooth and definitely metallic, though sharing the blade's bright silver appearance.
The Cogblade can be used to interrupt or cancel aetheric patterns, much like the Astral Breaker artifact category; however it can also rearrange patterns into something more desirable (assuming the wielder is skilled enough to accomplish it), avoiding the detrimental effects that come with repeated interrupts and cancellations. Judging by records of their movements, the inset gears seem to have something to do with the Cogblade's resistance to aetheric structural damage; however, their precise method of operation - like most of the blade's peculiar attributes - is unknown.
Although thorough analysis has been attempted on many occasions, the Cogblade itself seems to actively deny any but the most basic procedures, rearranging its physical/structural attributes to the bewilderment of onlookers. Whether this is a function of design or of some sentience residing within the blade has yet to be determined.
According to the Eighth Library's records, every civilization with knowledge of the Cogblade has by common use conferred upon its wielder the title of 'Cog Knight'. Oddly, no specific reason for this has ever been recorded.