The Sea of Simulation is a part of the server that is a giant digital ocean with patches of barren wasteland, mountains and other treacherous terrain.
In 1982, the Sea of Simulation had digital "bubbles" or spheres that slowly floated upward, which could be hazardous for vehicles flying through the sea. Another hazardous element the sea has are the gridbugs, insect-like creatures that cause glitches in the system.
The Sea of Simulation in 1982
1989
In the Tron system, the Sea of Simulation is located past the Outlands to the far right of Tron City.
2010
In 2010, After making eye contact with Kevin, Rinzler starts getting flashbacks of when he - as Tron - had saved Kevin from Clu then he states his iconic line "I fight for the users" then subseqently goes on to help Quorra, Kevin and Sam escape as he distracts Clu by trying to derez him and his light Jet. However Rinzler only manages to derez Clu's light Jet , The two then have a battle , in the ensuing battle however , Rinzler is pushed into the Sea of Simulation, His circuits then start flickering as they change from orange back to his natural blue color