The MagicKraftWerk (aka MKW for short) is an experimental heavy energy gun found by Red Sky and her companions in Deathwing's Castle.
In chapter 4, Red sky makes a description of the weapon
"The gun itself was within seven or eight kilos, like... a foal, maybe . The main colors of the weapon were dark blue-gray, black and silver with some yellow notes relative to the use of electricity and how it had to be used. The butt of the gun was simple, without extension. There was a kind of generator on the left side, positioned on the lower part of the weapon and there was a space, as if it missed something. Above the generator, which looked like a barrel, even if it was difficult to distinguish it from the rest of the machine.
I activated the secondary mode and the part above the generator opened, revealing a gap between two parts of the barrel with a slight magical activity between these parties.
Between the barrel and the generator, a sort of cable from the generator which was going above the butt and went fixing itself behind the gun. On the upper right, it seemed to lack some items that could be optional. The below handle of the gun was simple and retracted when I activated the primary mode."
The MKW has numerous upgrades in equestria which improve its capacities, damages and make it a more versatile and destructive weapon.
(No upgrades found yet)
As it was wrote on a letter from Princess Luna to the Überdirektor Sawbones, the MKW was a secret experimental energy gun from the Ministry of Wartimes Technology.
The MKW is owned by Red Sky and as Sawbones said, the MKW has severals upgrades all across Equestria.