The Lost Partition update adds a new kind of player progression, various items, new Programs on the Supercomputer (and by extension, the laptop) along with two new locations on Earth and new Tower processes (formerly known as tower protocols).
Knowledge system: allows for non linear progression in the server! Check what Knowledge you have from the Virtual Menu or by using the /lw knowledge list command.
CDs: CDs have been added and the CD reader of the computers have been made functional!
Hopper's Diary: Discover the story behind the creation of Lyoko in this update with the diary! But to get to the juicy details, you'll have to decrypt it first...
Tower Remote Control: Access the towers' processes, start new ones and activate them through this brand new program in the Supercomputer!
Supercomputer Energy: The supercomputer will now be able to hold 500 Energy to use in programs like the tower remote control. To recharge the energy, you can use the Sector Five terminal.
Takeover: Used by XANA to take control of your towers, prevent it from doing so with...
Safeguard: Hinders all control shifts over towers and pauses them. Costs 50 energy and only lasts for a few minutes so use it wisely...
Defense: An overshield that protects towers against physical attacks. Costs 50 energy and has half the tower's max health. Lasts until its time runs out or the overshield breaks.
Possession: Not exactly new, XANA already used it. The difference is that now you can use it too to defend yourself on earth against possible attacks too. Costs 100 energy.
Life Force Drain: If XANA successfully takes over a tower while possessing a player, they'll begin getting drained until death, so, for your safety, make sure to never take an eye off of towers while XANA is taking them over...
Diary Decryption: Pretty self explanatory, decrypts the diary while XANA attempts to take over, don't let it though or otherwise...
Data Breach Protocol: Occurs when XANA takes over a tower while a diary is being decrypted. Deactivate it swiftly or it's game over...
The train station is based on a real place: Train World in Brussels, Belgium.
The train station was built by our superbuilder, MATRIX, and builders ArronSkull66 and Mioka.
The Hermitage has actually been built for years, but has never been used until now. It was built by a retired builder named Robb (from the Code Lyoko: Return To The Past movie).
The coding part of the update was done by OscarKoala.