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Title: Probotector

Edition: Konami GB Collection Vol. 1

Media/Formats: Cartridge

Developer: Konami

Publisher: NTSC-J: Unreleased

NTSC-U: Unreleased

PAL: Konami

Release: NTSC-J: Unreleased

NTSC-U: Unreleased

PAL: 2000

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Despite technically being the PAL release of Konami GB Collection Vol. 1 from Japan, it was released for Game Boy Color instead and approximately 3 years later. The version of Operation C featured in this compilation is in fact the original Japanese version; however, it uses Probotector’s title screen, minus the copyright information. This special version of Contra features a limited color palette, often with questionable colors in certain areas. Save for the lack of the Konami logo before the title screen, there are currently no known differences with the actual game.



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See the Stages section of the original Game Boy version of Operation C.

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Operation C introduced (or at least standardized) the convention of automatically firing guns to the Contra series.

Powerups are acquired through certain objects and enemies scattered throughout the game.



-Unique occurrence, where an H powerup is hidden in an inactive enemy on Stage 4:


-Unique occurrence, where an H powerup is hidden in an inactive enemy on Stage 5:


Default Machine Gun:

New to the Contra series for a standalone game, the player’s default weapon is a Machine Gun. The player starts with this gun and, assuming they have a gun powerup, will revert to it when respawning after death. Rapidly fires bullets.

Spread Gun (S):


Shoots 3 large, powerful bullets that fan out. When upgraded, it then shoots 5 fanning bullets. Due to the handling of player bullets, excessive firing will cause the bullets to gradually lose their formation, spreading less and less. This is the only gun that can be upgraded, and it is done by acquiring another Spread Gun powerup (the same way as the arcade version of Super Contra).

Fireball Gun (F):


Shoots fireballs that, upon impact, explode into 4 smaller fireballs that spread diagonally out. Functions similar to the Fireball Gun from the NES version Super Contra, but does not fire a powered shot.

Homing Gun (H):


Introduced to the series is a homing gun. Shoots a barrage of bullets that very briefly fan out like the Spread Gun, but immediately seek out enemy targets. Repeated fire breaks down the spread formation and it then fires the bullets in single file. It is considered the best gun in the game. Its only drawback is that the bullets may fail to hit targets at crucial moments, costing the player their life.

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Most, if not all of the names provided here are unofficial. Due to the ambiguity of enemy names between regions, the lack of names for several of them and the absence of various documents, it is impractical to list the correct designations. Help is strongly encouraged and always appreciated to fill in these blanks. The Opposition section serves primarily to describe and depict the enemies for bookkeeping; thus, the content presented below hopefully satisfies this criterion.

Fodder Enemies, Objects

Exterior Unarmed Foot Soldier:


The weakest and most basic enemy. They predominantly run along sections of numerous stages. Occasionally, they jump off the edge of grounds in an attempt to chase the player, though this sometimes results in them falling to their death.
Found in stages: 1,3

Ubiquitous Standing Sniper:


They’re usually found on high grounds/platforms, such as thin towers and tree tops. These soldiers actively aim and fire at the player.
Found in stages: 1,3,5

Clothesline Turret:


Moves back and forth along the length of a thing beam, actively aiming and firing at the player.
Found in stages: 1

Disarmed Wall Turret:


Only one of of these turrets is encountered in the game. Embedded in walls continuing the surface of edges, they don’t fire bullets at the player.

This was likely intentional by the programmers and not a glitch, as the exact same turret placement pattern was first used in the NES version of Super Contra.
Found in stages: 1

Armed Wall Turret:


Embedded in walls continuing the surface of edges. They fire bullets at a slow rate.
Found in stages: 1

Sentry Drone:


Attack the player during the descending elevator segment of Stage 1. They extend out a retractable limb downwards, including diagonally, towards the player’s position.
Found in stages: 1

Assault Boat:


Small boats with 2 weapon components; both need to be destroyed to fully destroy the boat. In the front is a Port Turret that actively aims and fires bullets at the player’s position. In the back is a Double Mortar Cannon, which launches explosives 2 explosive shells in opposite, parabolic trajectories.
Found in stages: 1

Base Unarmed Foot Soldier:


Similar to the Exterior Unarmed Foot Soldier, these ones walk around the stage, following the player to reach them.
Found in stages: 2

Base Rifle Foot Soldier:


Similar to the Base Unarmed Foot Soldiers, but these ones occasionally stop to fire 2 bullets at the player’s immediate position.
Found in stages: 2

Base Smart Turret:


Able to aim in 8 directions, actively fires bullets at the player’s position.
Found in stages: 2

Base Standing Sniper:


Actively aim and fire shots at the player.
Found in stages: 2

Conveyor Turret:


They have 4 gun barrels arranged in an X motif. Between intervals, the barrels fire a bullet, one after the other, clockwise from the top-right. They slide move up and down along a short length of their track. Destroying all of them deactivates the Conveyor Belt Floor that slows the player down.
Found in stages: 2

Steel Barricade Double Door:


Large wall-like door that blocks the player’s progress, located immediately before the Train Tank. Takes a large number of shots to break and is vulnerable only close to the mid-line.
Found in stages: 2

Ground Turret:


Springs out of the ground when approached and fires bullets. Occasionally, it retracts for a few seconds before rising out again.
Found in stages: 3

Falling Boulder:


Bounces down along the mountain/waterfall rock walls.
Found in stages: 3

Waterfall Smart Turret:


Able to aim in 8 directions; actively aims and fires bullets at the player’s position.
Found in stages: 3

Scuba Soldier:


For the most part, they remain in the water with their head emerged. On occasion, they rise partly to fire bullets; they are vulnerable only in this phase.
Found in stages: 3

Drone Bug:


Spawned from the Armored Alien Hovercraft, they drop to the ground and simply run left or right across the screen.
Found in stages: 3

Pulsing Bubble:


Shot from the Alien Hovercraft; as its name implies, it is a bubble-like organism that pulses and flies straight in certain directions.
Found in stages: 3

Beetle Egg Sac:


A large, pulsing alien egg that bursts in 2 possible ways: if shot enough times or when approached/bypassed. Upon bursting, 3 Alien Beetles spread out from it.
Found in stages: 4

Alien Beetle:


Hatched from Beetle Egg Sacs, these creatures crawl along the floor in a general direction, occasionally turning slightly.
Found in stages: 4

Alien Cockroach:


Large, cockroach-like aliens that stop crawling periodically to spit out 2 Cotton Balls.
Found in stages: 4

Cotton Ball:


Organisms with several hair-like pseudopods; they move in somewhat eccentric arcing/circular patterns and die off after a few seconds.
Found in stages: 4

Alienated Foot Soldier:


Functionally identical to the Exterior Unarmed Foot Soldiers.
Found in stages: 5

Ceiling Turret:


These turrets alternate between opened and closed states; in the latter, they are vulnerable and fire fast bullets diagonally downwards.
Found in stages: 5

Face Hugger:


Alien arachnids that break out of large glass tubes; they crawl on the ground.
Found in stages: 5

Embryo Bubble Dispenser:


Organic domes embedded in the ceiling. They’re immune to damage when closed; however, they periodically open up to deploy several Embryo Bubbles, during which they’re vulnerable.
Found in stages: 5

Embryo Bubble:


Dropped from Embryo Bubble Dispenser, these organisms hover left/right across the screen.
Found in stages: 5


Spread Fire Tank:



Moves left and right, with 2 Triple Turrets that fire alternatively. The Triple Turret, as its name implies, fires 3 large bullets in a spread formation. This mini-boss is fought multiple times, each in a slightly different situation. One of these situations is the stage’s boss battle itself, the Train Tank.
Found in stages: 2

Armored Convoy:


Initially seen parked and harmless, this vehicle catches up and ambushes the player a short distance later. Its side hatch is open, occasionally deploying Base Unarmed Foot Soldiers. At the top, there are 3 compulsory components. In the center is a Mortar Cannon that launches explosive volleys in an arc. Flanking it on either side are Dual Turrets. These alternate between opened (vulnerable) and closed (immune) states; in the former, it fires 2 bullets that narrowly spread out.

Once this mini-boss is defeated, enemies stop deploying from the open hatch.
Found in stages: 2

Armored Alien Hovercraft:


Hovers up and down above the player, moving left and right; occasionally stops moving to deploy a pair of Drone Bugs, one from each side. During the battle, Exterior Unarmed Foot Soldiers spawn from the left and right sides of the screen. When it’s defeated, it loses its ventral armor attachment and flies off.
Found in stages: 3

Laboratory Guardian Mech:


A large, armored robot that is able to hover. Initially, it floats back and forth to the left and right sides of the area, lands down and launches missiles from its thoracic segment. When weakened, it launches its hand attachments, which curve down before flying up and clinging to the ceiling; after a sequence of rockets, the hands return in the same trajectory back to the mini-boss. It repeats this new pattern until defeated.
Found in stages: 5


Small Missile Submarine “Nouel”:


Consists of optional and compulsory components. Flanking the compulsory components, an optional Port Turret is placed on either side. To the right of the leftmost Port Turret, there are 2 Torpedo Pads; they remain closed and immune to damage most of the time, occasionally opening up to launch a torpedo straight up, at which point they are vulnerable. Next to them is the Sub Turret, that also opens and closes in the same pattern and is immune/vulnerable in the same way; it fires bullets diagonally up-right when it opens up. Next to the Sub Turret are 3 more Torpedo Pads.

The Submarine follows a preset pattern where its components attack at least twice, after which the boss submerges in the water temporarily. During this period, Exterior Unarmed Foot Soldiers appear from the left and right.
Found in stages: 1

Tank Train:


A chain of 3 machines that repeatedly moves left and right. The center component, Blaze Tank, is the goal of the boss battle; it contains a vital core that fires large blaze projectiles at a slow rate. The machine alternates between sealing the core (protected) and opening up to allow it to attack (vulnerable).

Also functioning as a connector, a Spread Fire Tank is attached to the left and right side of the Blaze Tank. The Blaze Tank can be damaged only after the flanking tanks’ turrets are destroyed.
Found in stages: 2

Alien Hovercraft-Dock Combo:


The previously damaged Armored Alien Hovercraft returns and attacks with assistance from the Alien Turtle Dock.

The Alien Turtle Dock is optional. It moves left and right on the ground across the screen, with sharp horns on each side. It also holds a Dock Turret, that open and close, on either side; the turret is vulnerable only when it opens up to fire a bullet. The player can safely stand on top of this alien creature.


The Alien Hovercraft now sports a pair of the same Extending Limbs as those of the Sentry Drones. Once both are destroyed, the craft will periodically expose its Organic Core, the main goal of the battle, which fires 4 Pulsing Bubbles; the core is vulnerable when exposed. On occasion, the hovercraft also docks atop the Alien Turtle for a few seconds.
Found in stages: 3

Alien Queen Arachnid:


Strafes left and right, using 2 attacks periodically. Its posterior extremity emits a beam that bounces off the edges of the screen a few times before leaving the screen. Its anterior mouth spits out 3 Cotton Balls.
Found in stages: 4

Cellular Embryo:


Final boss of the game, a completely harmless organism in a glass tube that is out of reach of the player by a large Death Pit. It must simply be fired upon. As it receives more damage, the organism pulses faster and the glass becomes more cracked.
Found in stages: 5

Other Dangers

Death Pit:


As the name implies, falling into these kills the player. Some are deep pits that make for a very high fall and a usually unknown or inescapable landing area. Others contain a deadly surface or a pool of dangerous substances.
Found in stages: 1,3,5

Conveyor Belt Floor:


While these don’t pose a direct threat to the player, they slow down progress and can make it easier for enemies to kill the player, especially the ones that fire.
Found in stages: 2

Extending Alien Limb:


Rapidly extend from lumps in the alien architecture. Their somewhat unpredictable patterns can make them difficult to avoid.
Found in stages: 4

Electrical Beam Outlet:


Installed on walls, these devices emit a pair of Electrical Beams, each from a different altitude. The outlet itself is also deadly upon contact.
Found in stages: 5

Electrical Beam:


Emitted from outlets installed on Stage 5’s elevator walls.
Found in stages: 5

Electrical Fountain:


Several of these traps line the path to the Cellular Embryo; the laboratory is fitting with floor and ceiling attachments that occasionally form a column of electricity.
Found in stages: 5

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Input the following codes on the title screen, when asked to press START.

10 Lives: Press UP, UP, DOWN, DOWN, LEFT, RIGHT, LEFT, RIGHT, B, A, B, A, START. The player will have 10 lives when starting the game or continuing after a Game Over.

Sound Test Menu: Press UP, DOWN, LEFT, RIGHT, A, B, START.

Level Select Menu (Redundant): NOTE: This code is pointless in this version since it features the Level Select menu by default; however, inputting the code plays a confirmation sound.

Hidden Elements

Hidden Homing Gun Powerups: Approximately 2/3 of the way into the fourth stage, there is a dormant egg on the left side. It contains a Homing Gun powerup. Atop the first climb on the fifth stage, there is a facehugger that does not break out of the display tube. This tube contains another Homing Gun Powerup.

Easily Cross the Bridge: Just before the stage 3 boss, there is a gap that is very difficult to cross. Wait 20 seconds and a bridge will form over the gap, eliminating the risk of getting killed.

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See the PAL plot of the original Game Boy version of Operation C.

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See the Soundtrack section of the original Game Boy version of Operation C.

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There are currently no known variants of this port of Probotector for Game Boy Color.

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The Game Boy Color version of Konami GB Collection Vol. 1 was released only in Europe.

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There is currently no known developmental material to present.

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See the Technical Information section of the original Game Boy version of Operation C.

-This port of Operation C (Contra) is essentially the Japanese release with a Probotector title screen (different from the original PAL release, however). It runs on the same hardware, but with a limited color palette applied.

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See the Trivia section of the original Game Boy version of Operation C.

Violent Probotector:
Operation C is a special case in the Contra series. It is the only Contra game where one of its Probotector counterparts, this port, is uncensored. In other words, this is the only Probotector game in the entire series to not feature robots or other forms of censorship. In addition, this is technically the first Contra game to not feature robots in the PAL release.

Origin Of recurrence:
This game can be considered the first in the series to reuse bosses from previous Contra games.

The first tank mini-boss battle in stage 2 is very similar to the tank mini-bosses in stage 2 of Super Contra, including its attack:


Stage 3’s mini-boss shares some similarities to NES Contra’s stage 5 boss:


The final “boss” is a pulsing alien organism defended only by the glass tube in which it’s enclosed:


Despite bearing more resemblance to several final battles in the Gradius series, the setting is also comparable to the final boss of the original Contra.

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-Review/ad page from issue 216 of Computer and Video Games:


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Operation C main page

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