Excision

Excision is a substratic blade-like melee weapon developed by the Black Research Substratics Unit (BRL-11) from reverse-engineered Precursor technology. It cuts through all nearby dimensions at once, bypassing phasers, forcefields, and fractal armour. Capable of causing permanent damage to dimensional manifolds, it is illegal to use under the Dimensional Security Accords except in defence of reality during a calamity. It is the only weapon able to harm some sapient anomalies at maximum threat level, including Exon and the Selerian Horror.
Effects
The Excision weapon is made of partially reactivated Precursor nanobots. When activated, the blade is projected from the sheath, appearing as a starfield with a static position relative to that of the sword. The edge works similarly to a grid control system; it exerts control over reality in the space the blade passes through, both slicing and cauterising the connections within the substratic network that backs the local manifold. This leaves a physical "tear" in the manifold that entropy then floods through, ripping it apart and causing even more chaos.
When swung through the physical form of a conscious entity (i.e. Exon), due to this effect it not only wounds the manifold making it up but also the network that hosts its consciousness. This can damage psionic abilities, induce hallucinations, and even eventually cause total and permanent collapse. Powerful psionic entities like Exon can recover from substratic damage given enough time, but for other sapient entities, this is usually an instant death sentence.