Quad Rotary Cannons

FIREARM RARE VEHICLE WEAPON LARGE SILENT PIERCING

Four small cannons with rotating barrels that can be fitted underneath an Ornithopter. Fires 4 times per attack.   Gunner. If you have Firearms proficiency and are familiar with the controls you can add your Proficiency Bonus to the attack roll.   Multi-purpose. Can be fitted to any vehicle weapon slot of the appropriate size.   Rotator Gun (Spinning up). Make 4 attacks. To hit: 1d20 + Proficiency Bonus (Firearms) + Dexterity Modifier, on hit: 1d10 + Dexterity Modifier. Full spin: After the first turn the barrel is rotating at full speed. You make 5 attacks instead.  

Special attack

Strafe. Dive and spin up both barrels to maximum rotation. In a 100 ft. long, 5 ft. wide line, creatures must make a Dexterity Saving Throw DC12 or if you have Firearms proficiency and are familiar with the controls DC8 + Proficiency Bonus + Dexterity Modifier, whichever is higher, on failure they take 8d10 Piercing damage, on success half damage. After this attack the guns need to cool down for 1 full turn before you can fire again. The gun stops spinning and loses the Full spin feature.