B2-SRT Laser Cannons

The arm-mounted laser cannons of a B2 Super Rocket Trooper. Introduced as part of Baktoid's B2 Regenesis Program, complimenting the B2-SRT Thruster System to complete the B2-RP to B2-SRT upgrade process, the pair of quad-barreled laser cannons replace the standard B2 wrist blasters on each arm; at the cost of also replacing the B2-RP's wrist rockets. 

You have a +4 bonus to attack and damage rolls made with this weapon. This weapon has the following properties:

Multi-Barreled. This weapon has four barrels, double that of a standard B2's wrist blaster, and thus deals an additional 3d6 Radiant damage with each use. 

Hull Breach Mode. As a bonus action, the arm cannons switch from their standard firing mode to a specialized firing mode designed to breach the hulls of enemy ships. Upon firing, the arm cannons unleash a concentrated beam of energy forming a line 5ft wide and up to 75ft long. Each creature caught in this line must succeed a Dexterity saving throw, the DC being 9+Proficiency+Dexterity, or take 4d12 Fire damage plus 4d12 Radiant damage. Constructs hit by this beam take damage as if they were Vulnerable to both damage types. However, the necessary power paired with the monumental energy output means that the arm cannons require a cool-down period of 2 Turns before they can be safely fired again. 

It’s up to you to decide whether a character has proficiency with a firearm. Characters in most D&D worlds wouldn’t have such proficiency. During their downtime, characters can use the training rules in the Player’s Handbook to acquire proficiency, assuming that they have enough ammunition to keep the weapons working while mastering their use.

Notes: Bonus: Magic, Damage: Radiant, Baktoid Combat Automata mechanist, or otherwise qualified Droidsmith, who installs the upgrades over the course of an hour-long maintenance session., Damage, Combat, Range, Ammunition (Firearms), Reload, Vex