Together, the Bolboros duo fires lasers. The smaller core will fire similar to Big Core MK I, while the larger will attack with covering fire. They don't seem hard until you destroy one of the cores. If you destroy the big ship, the small ship will freak out, opening it's two "shoulder blades" and firing streams of tiny bubble bullets. These "shoulder blades" can be destroyed if enough firepower is concentrated on them. If you destroy the small ship, the big ship will start moving around, firing lasers every time it stops. The small blue laser emitters can also be destroyed, lessening the amount of fire coming your way. Eventually, it will trap you in the middle of the screen, while (on loop 2) firing laser streams, and will also fire a large red laser. There is a safespot for this laser, right in front of the core, just like the final gun wall in Gradius: The Interstellar Assault. However, the laser's kickback can be problematic.