System Defender
System Defender Logo
Players 1
Controls Mouse
Minigame location EPF Command Room
Date released January 14, 2011[1]
Date closed March 30, 2017
For the adventure from Club Penguin Island, see Ep. 8 - System Defender.

System Defender was a game and a security system for the Elite Penguin Force, launched on January 14, 2011.[1] All EPF Agents could play this game in the EPF Command Room. It was used to defend the EPF Mainframe computer from threats. System Defender was a Tower Defense game.


Red cannon

The red cannon shot fast, but was weak in terms of damage. Cost 50 energy, and was best used for the beginning of all levels.

Yellow cannon

The yellow cannon had a long range, a moderate damage output and firing speed. Cost 125 energy and was best used in places where red and purple cannons would not be able to hit bots.

Purple cannon

The purple cannon did considerable amounts of damage, but shot slowly. However, it would deal a fatal blow to each bot it hit. Cost 200 energy, and was best used against purple and boss bots.


Gears were items used to upgrade cannons. They were sometimes dropped by boss bots, or could be purchased for 500 energy. When used on red cannons, they added more shots per hit. For yellow cannons, they increased damage and range. For purple cannons, they increased damage and added mini shots, which did a fair amount of damage. The added shots were somewhat faster than the regular shot of the cannon.


Red bots


Red bot

  • Red bots attacked in large groups.
  • Best suited cannon: Red, because they could deal damage over a huge area by blasting away quickly.

Yellow bots


Yellow bot

  • Yellow bots were fast.
  • Best suited cannon: Yellow, as their projectiles did not need time to reach destination bot.

Purple bots


Purple bot

  • Purple bots could take lots of damage.
  • Purple bots were slow.
  • Best suited cannon: Purple, as their beam of energy was concentrated and powerful, and high rate of fire was not necessary.

Boss bots

Boss bots were larger, harder to destroy and did more damage than regular bots. Sometimes, when destroyed, they dropped a gear which could be used to upgrade cannons.

Ultimate Proto-Bot 10000

The leader of all bots. It was also in Club Penguin: Elite Penguin Force and was rebuilt by Herbert P. Bear. The Ultimate Protobot was also capable of scanning the layout that you have placed, creating attack patterns that would be harder for you.

Herbert P. Bear

He was the source and rebuilder of the Ultimate Proto-Bot 10000 and also controlled all the small bots.

Test Robots

The Test Robots were supposedly rebuilt by Ultimate Proto-Bot 10000.


Klutzy mistook Herbert's computer with an arcade, and attacked the EPF.


Challenge 38/100

Enemy bots are attacking the EPF mainframe computer. But who is responsible?

Challenge 47/100

Herbert P. Bear is back to destroy the EPF. Can you stop him in time?

Challenge 54/100

The EPF faces one of its toughest challenges when it is attacked by... Klutzy?

Challenge 73/100

The Test Robots are attacking all at once. Can you outsmart all three? (members only)

Challenge 96/100

RED ALERT! The Ultimate Protobot is attacking the EPF mainframe. Battle Stations! (members only)

Challenge 100/100

TRACK HERBERT!!! Herbert is back with more tricks up his sleeve. Can you face him?


At the beginning of the game you had a starting amount of 200 energy. Sometimes enemies dropped extra energy, which could range from 5 to 50.

Weapon prices

  • Red cannon = 50 energy
  • Yellow cannon = 125 energy
  • Purple cannon = 200 energy
  • Gear = 500 energy


Main article: List of System Defender Stamps


  • You had to use the 200 energy at the start to make 4 red cannons, except for the "Track Herbert" level, where you had to put up 1 purple cannon on a corner.
  • U-turns and corners were the places where the red cannons had to be placed.
  • Once most of the u-turns and corners were filled with red cannons, it was recommended to build yellow cannons separated evenly by each other.
  • You had to build multiple groups of yellow cannons clustered in groups of 2-6. Yellow cannons were extremely good at protecting the system from huge waves of bots.
  • You had to build purple cannons when the bosses started appearing in huge groups. They were the perfect anti-boss weapons.
  • When upgrading, you had to upgrade one cannon fully before upgrading the next.
  • It was recommended to completely upgrade each cannon.


  • Rookie was the cause of some robots, due to him accidentally opening a jar that was labeled "COMPUTER BUGS", when he mistook it for, "COMPUTER HUGS".
  • You could earn 1 medal when you stopped a threat for the first time. You could not receive one after beating a previously beaten level.
  • This game was the first appearance of the Ultimate Proto-Bot 10000 in the online Club Penguin.
  • Formerly, in the Stamp Book page for this game, one of the pictures required a higher amount of stamps than the amount of stamps that existed, as it required 16 stamps whereas there were only 14 in the game. This was later changed to 14 stamps for the picture to appear. The missing stamps were the Strategic 318 stamp and Energy 9999 stamp.
  • There was a Card-Jitsu card named Enemy Bots, which depicted the three bots in the game, along with an unseen fourth bot. It was spherical and dark black, with navy blue colored eyes. A portrait for this bot also appeared in the game's files, along with the other portraits.
  • When initially released, System Defender's label said **system_defend** when hovered over. This was later fixed.


Names in other languages

Language Name
PortugueseDefensor do Sistema
FrenchDéfenseur de Système
SpanishDefensor del sistema
GermanSystem Defender
RussianКибер защита



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