In its debut appearance in Contra, Godomuga are actually a pair of hovering automatons capable of creating "phantom" duplicates of themselves. Each of the devices is only vulnerable when its two phantom images have merged with each other. They attack by launching homing projectiles that follow the player in a looping arc. Both Rangel and Garth infantry units will be constantly entering the fight to assist the boss.
Once one of the Godomugas has been destroyed, the remaining one will become more aggressive and start churning out even more projectiles at a faster rate; therefore, when only one is left, defense becomes more important than offense and the player is advised to destroy the remaining device as quickly as possible.
In Contra 4, Godomuga reappears as the boss of the third level, Base, being a single device this time around. It periodically splits into two virtual blinking images that initially separate a short distance before retracting and merging again. They merge at a different spot each time. All heads, whether merged or virtual, emit bubble dimers. After sustaining enough damage they will take longer to merge, moving around and crossing over each other a few times before doing so.
In the first phase, the boss is vulnerable only in the single, merged form. At the beginning of the encounter, four Darrs will be periodically dispensed from four holes at the base of the wall. Afterward, only two will be dispensed at a time from holes that are selected randomly. In addition, base security soldiers will be occasionally entering the screen throughout this phase.
After sustaining enough damage, phase two begins. Here, the boss stops forming virtual images and instead it will start to rapidly move left and right, emitting dimers more frequently. All other enemies will stop appearing and the boss will now be permanently vulnerable.