The Mythril Blitz is the cannon obtained from the crafting of 7 Mythril Chunks. It is a relatively weak cannon for its calibre, dealing only 27 ranged damage. It consumes Mythril Dust as ammunition and has infinite uses. It is a weak and expensive weapon, so it is not recommended to craft this weapon.
The mere fact that it is weak and expensive to craft weapon makes it pointless to obtain. Although it has infinite durability and a high rate of fire, the fact that it requires ammunition limits this advantage. A much more suitable weapon to obtain would be the Mythril Phaser. Even a lower tiered weapon such as the Queen of Ice is a better option compared to this, dealing the same amount of damage as well as inflicting a slow effect.