Commissar Gabbet smiled as his guardsmen were cut down. The troops tried to fight back, but close quarters vrs a space marine was not a very fun option.
He hated those new recruits anyways.
While Shiro was distracted and his troops distracted, the once concealed heavy bolter positions, stocked with Real Veterens, equal to a relatively new space marine experience wise, opened fire from above, cutting down marine after marine in controlled bursts of explosive automatic rocket launcher. His force designed the trenches to be easily destroyed from ranged fire on both sides, and the Assault Marines took the bait and took the worst of the machine guns fury.
He chuckled as he saw a sniper hurtle to the ground in front of him from the explosions, and break most of his body.
The man still yet lived. Gabbet arranged for a change, and stabbed the man in the face, and grabbed his bolter.
Still in pristine condition... as usual for all space marine technology.
He fiddled around with it as his soldiers were fighting and dying and accidentally pulled the trigger, accidentally killing the last recruit that he hated in the process.
"That was fun!" he said before dropping the bolter, and melting a marine's assault pack with his plasma pistol, causing him to fly out of control in a very funny fashion.
the 105th Mad Gabbers were doing pretty well for an Imperial Guard regiment.