I am cleaning the ground with artillery in the extraordinary world

Chen Miao traveled to a supernatural world, where everyone has their own profession, such as "student", "fighter", "thief", etc.
After careful consideration, he activated the "Gunner" profession.
After this!
While the aliens were flexing their claws to launch an invasion, others were working hard to practice their physical fitness and learn skills.
Chen Miao silently went to the secret realm to collect various materials to create professional-specific weapons such as "Thomson submachine gun", "Falling Flower Sniper Rifle", "Inferno Gatling" and "Matrix Sky Eye Cannon".
...
One day, everyone suddenly discovered that an extremely unfamiliar extraordinary profession had appeared on the city's combat power rankings.
And in the crowd.
Chen Miao, who was shirtless, wearing a black suit jacket and sunglasses, had a cigar in his mouth and two Purgatory Gatling guns in both hands. He looked at the crowd of young men in front of him, with the corners of his mouth raised slightly.
"Don't wait until I put the muzzle of a gun in your mouth before you say you're wrong."