[quote=gamer5]1. Ewera actually worked in a team; most of the inventions that were made during her stay in Wintra were made with her as a part of the team. The Razor is one of the rare inventions that Ewera made by herself (as a request for a heavy-duty stone cutting tool).[/quote]
I was aware of that. But that doesn't mean it takes a short period of time. For some real-life comparisons, it take 2-3 years for a company to develop a new car, 5 years to invent the M1 Abrams tank, and about 1 year to invent the AK-47. If you go into novel or little-explored technology, such as weapon lasers and immaterial blades, you can easily add a year or more on top of that. As I said, it's not quite impossible, just rather difficult. An extra two years would make a lot of difference.

On a specific note, the Blaze laser would still get hotter than a propellant firearm, especially since the beam needs to be concentrated somehow. Perhaps the heat (and damage) would be comparable to a fire core weapon instead, except being a laser it can be fired continuously but it would get much hotter that way. I'd suggest a water-core-powered liquid cooling system could cool it enough to avoid having it overheat too quickly. It would be reasonable for it to slowly cut through metal, given breaks every few seconds.

P.S. In my personal opinion, a whizzing beam of diamond dust, even with kinetic cores, doesn't sound any more effective at cutting than a chainsaw and has the con of requiring both sides of the object you are requiring to cut to be within reach. But that's just my opinion. There exists no information about the cutting power of grains of diamond propelled by magical stones.