I have made some ideas.
Sanguine Channel: A weapon fueled by blood and Dust. Sanguine Channel's user will not be able to bleed out if they are attacked underneath their Aura, as a sufficient amount of blood will consistently remain inside the user. Sanguine Channel is shaped like a single-edged blade, but it can morph into a scythe-like contraption to drag in enemies or swing targets around like ragdolls. Sanguine Channel requires the user to have the Sanguine Gauge Semblence, which allows the user to mix Dust with the user's blood to create gelatinous layers over the Sanguine Channel. These layers have different effects based on what Dust was mixed into the Channel, but does not necessarily follow the primary elements of magic (ie. mixing Fire Dust with the user's blood will create an acidic coat that could sear through organic parts of Grimm; ineffective versus armored targets)
Iron Maiden: A suit of armor that transforms into a triple axe-bladed jetboard roughly shaped like a gigantic square shield. The Iron Maiden's Suit form automatically overcharges safely when explosives are used against it. The Suit trades range for total defense using the Iron Maiden's highest offensive equipment. A speeding truck will lose against a direct confrontation with the suit of armor. The Jetboard form of the Iron Maiden can be spun around, effectively creating a spinning wheel composed of three large axes. Two shotgun rifles are hidden within the contraption. The Jetboard regularly hovers over any surface it touches, but when any kind of Dust is applied to it, the Jetboard will be able to soar through the skies, albeit in a particularly loud-a-s fashion.
Masamune: A very powerful blade that has no ranged weapons loaded into it. When Masamune slashes through Dust, the Dust will turn into a vortex of nothingness that sucks in other Dust with great force. If Masamune is empowered by the user's Semblence, Arbiter, the user will gain the ability to strike through anything, in exchange for no longer being able to counterattack Dust attacks for several minutes. Arbiter allows the user, if careful enough, to let Masamune completely absorb Dust rather than destroying it. Whenever Masamune consumes Dust, however, nothing happens.
Cacophanys: A Dust-powered phone. When the phone is turned on, Dust comes out of the phone, and the phone can be held like a one-handed blade. The phone, however, can run out of batteries. While it does have limited usage compared to many other weapons, it boasts an incredibly lightweight, yet hard-hitting beam of Dust. The beam of Dust is able to be contained by a small contraption puts a "mirror" at a distance from one of the phone's edges, allowing a phone-screen-sized blade to retain its shape as long as enough Dust is being used. If the user shakes the phone once it runs out of batteries, the phone will use a backup energy source that is not as strong as its Dust weapon form. Different kinds of Dust gives the phone different attack abilities.
These are not the last of my ideas, but they are some of my first ideas. Feedback would be appreciated.