The Forest Replika was first discovered in Maiden Voyage, when the Lyoko Warriors tested the Skidbladnir for the first time and got lost in the Network. When they first came across it, Odd and Ulrich mistook it as Lyoko because it looked exactly the same but Aelita quickly confirmed it wasn't Lyoko. The fact that it was a Replika and not Lyoko was confirmed by Jeremie near the end of the episode. Like most of the Replikas, it is speculated that X.A.N.A. created it using the Keys to Lyoko it stole from Aelita in the Season 2 finale.
However, the team didn't go there up until the episode Replika. They then found out that the sphere was a direct copy of the Forest Sector. Aelita was confused as to why would X.A.N.A. create another Lyoko. In order to explore it, the team separated, with Aelita and Odd being on watch for the Skid while Ulrich and Yumi investigate it.
In Lab Rat, the group found out the supercomputer that X.A.N.A. uses to run this replika is located in a Laboratory in the deep Amazonian Jungle. The Supercomputer was located inside of this laboratory.
- Jeremie tested his Translation program for the first time here.
- In Lab Rat, William entered the tower used to translate Odd and Aelita and enter Code X.A.N.A. to break the connection of the Skid with the tower, thus stopping the Translation. This is the only time where he entered the code in the series.
- This is the only Replika in which all four of the Lyoko Warriors have ever been transported to.
- The Forest Replika also makes an appearance in the game Code Lyoko: Quest for Infinity. There, the player must defeat a boss called the Insekt Lord in order to destroy the Replika.
|Ice Sector | Desert Sector | Forest Sector | Mountain Sector | Carthage|
|Ice Replika | Desert Replika | Forest Replika | Mountain Replika | Volcano Replika | Carthage Replika|
|Other Virtual Worlds|
|Digital Sea | Cortex | Virtual Limbo | Simulation Bubble|
|Dormitory Building | Administrative Building | Cafeteria | Gym | Track | Park | Hermitage | Science Building | Playground | Garden Shed | Infirmary | Boiler Room|
|Union Base | New Mexico Research Facility | Space Station | Jungle Research Facility|
|Renault Auto Factory|
|Factory Floor | Factory Lift | Lab | Scanner Room | Supercomputer Room | Assembly Room | Security Center|
|Kadic Academy | The Sewer | The Factory | Ishiyama residence | The Pool|