Club Penguin Rewritten Wiki

System Defender was a tower defense-style singleplayer game in Club Penguin Rewritten that was playable in the EPF Command Room. It was set in the EPF Mainframe Computer where you had to defend it from threats.


The game had six levels to choose from:

Level # Briefing Main Enemy Stamp
1 Enemy bots are attacking the EPF mainframe computer. But who is responsible? Enemy Bots (released by Rookie by accident) Bug Overload
2 HERBERT ATTACKS! Herbert is set on destroying the EPF. Can you stop him in time? Herbert P. Bear Herbert Attacks
3 The EPF faces one of its toughest challenges when it's attacked by... Klutzy? Klutzy Klutzy Attack
4 The Test Bots are attacking all at once. Can you outsmart all three? Test Bots Test Bot Trio
5 RED ALERT! The Ultimate Protobot is attacking the EPF mainframe. Battle stations! Ultimate Proto-Bot 10000 Protobot Attack
6 TRACK HERBERT! Herbert P Bear is back with more tricks up his sleeve. Are you ready to face him? Herbert P. Bear Track Herbert


Red Cannon

The red cannon shot fast but had low damage. It costed 50 energy and was best used for the beginning of all levels.

Orange Cannon

The orange cannon had a long range but only dealt moderate damage and had moderate firing speed. It costed 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 could do a considerable amount of damage, but fired slowly. It dealt a fatal blow to each bot it hits. It costed 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, but they could be bought for 500 energy. When used on red cannons, they added more shots per hit. For orange cannons, they increased damage and range. For purple cannons, they increased damage and add mini shots, which did a fair amount of damage and were somewhat faster than the regular shot of the cannon.


Red Bots

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

Orange Bots

  • Orange bots were the fastest bots but had low health.
  • Best suited cannon: Orange as it had a large range and can hit more bots.

Purple Bots

  • Purple bots could take lots of damage but were slow.
  • Best suited cannon: Purple as its beam of energy was powerful and you did not need a high rate of fire.


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
  • Orange Cannon: 125
  • Purple Cannon: 200
  • Gear: 500


  • Use the 200 energy at the start to place 4 red cannons, except for the "Tracking Herbert" level, where you had to put up 1 purple cannon on a corner.
  • U-turns and corners were the best places to put red cannons.
  • Once most of the U-turns and corners were filled with red cannons, the player could build orange cannons separated evenly by each other.
  • Build multiple groups of orange cannons clustered in groups of 2-6. Orange cannons were extremely good at protecting against huge waves of bots.
  • Build purple cannons when the bosses start appearing in huge groups. They were the perfect anti-boss weapons.
  • When upgrading, upgrade one cannon fully before upgrading the next.
  • Try to completely upgrade each cannon.


Some levels included Elite Medals as rewards; all included coins and stamps.



Image Name Description
Garbage Disposal Stamp.png Garbage Disposal Destroy 100 enemies in 1 level
Bug Overload Stamp.png Bug Overload Protect the EPF mainframe from rogue bugs


Image Name Description
StrategicSuccess.png Strategic Success Destroy 100 enemies without upgrading cannons
Mono Mechanic.png Mono Mechanic Complete a game with only one type of cannon
Tactical Pro.png Tactical Pro Destroy 100 enemies without taking damage
Master Mechanic Stamp.png Master Mechanic Fill every open socket with a cannon
Herbert Attacks.png Herbert Attacks Complete the level 'Herbert Attacks'
Klutzy Attack stamp-1.png Klutzy Attack Protect the EPF mainframe from Klutzy


Image Name Description
Strategic Master.png Strategic Master Destroy 250 enemies without upgrading
Tactical Ace stamp.png Tactical Ace Destroy 250 enemies without taking damage
Test Bot Trio stamp.png Test Bot Trio Protect the EPF mainframe from the Test Bots
Protobot Attack Stamp.png Protobot Attack Protect the EPF mainframe from Ultimate Protobot


Image Name Description
Track Herbert Stamp.png Track Herbert Complete the level 'Track Herbert'


  • The Ready For Duty Stamp was removed from the game as of January 24, 2018. This was due to a glitch that made it unavailable to all players, which was never fixed.
  • The last Stamp Book polaroid of System Defender couldn't be seen until November 8, 2019. The required stamp amount for the last polaroid was reduced from 16 stamps to 13.
  • The level briefing for level five was a reference to the "Red Alert!" line from the Star Trek franchise.
  • System Defender used to be more difficult due to Club Penguin Rewritten running at a higher frame rate than Club Penguin, making it run faster than it should. This also affected Pizzatron 3000. It was still possible to complete, although extremely difficult. The frame rate was lowered on January 10, 2020.





Level layouts