System Defender is an adventure in Club Penguin Island. It is received from Aunt Arctic, and is the eighth episode in Chapter 2: Shocking Secrets. During this adventure, the player must combat a computer virus sent by a Herbert to cause havoc.
The adventure starts with Gary informing the player that, after scanning for damage as Aunt Arctic mentioned in the previous adventure, he tracked down a virus Herbert placed on Aunt Arctic's computer, named the "CryptoSnoop 2.0", which was being used by Herbert to eavesdrop. However, Gary was able to find a weakness in the code, and requests the player contain the virus so he can recode it to listen in on Herbert instead. To do so, the player must slide a green circle, blue square, pink pentagon, and teal diamond on a grid to fit in corresponding slots. After all are in their correct slots, Gary recodes the virus, but a stronger signal is needed. Gary gives the player three transmitters to place at elevated locations, and hover platforms to reach said locations.
The first detector must be placed on the crow's nest of the Migrator, the second above the entrance to the Sea Caves (accessed from the zipline by the ruins), and the third inside the Sea Caves, (accessed by bouncing off the springboard on the balcony). After all three are placed, Gary uploads the virus into Herbert's system, and audio from his lair starts being received. Herbert states his voltaic ray is nearly charged, and he will gain control of the island soon. Aunt Arctic comments that there is little time to spare, but final preparations must be made first. The player then receives the Herber-tech Gadgetunique item, 50 coins, and 150 green XP.
Received from Gary after he recodes the virus. The transmitters are to be placed at three elevated locations to increase the signal of the virus, and the platforms are used in order to reach elevated locations where the detectors are to be placed.