I felt the need to post as the original post didn't mention any specifics and left it all to a link, which will eventually die making the answer not as good, so I added the info in another answer to maintain the reliability of the question's answer(s). Main source (among the others listed and my own knowledge). Multiplayer was added to War of the Lions. Additional side quests involving Agrais, Alicia, Lavian (Agrias' Knights), Beowulf, & Reis. More on the Dark Knight, Fell Knight, and Onion Knight on their wikia pages. The Onion Knight is not allowed any abilities (class & secondary) but is able to equip any equipment including the famous Onion Knight equipment. The Dark Knight is an obtainable job (This is not to be confused with the original's Dark Knight, Gafgarion which is now called Fell Knight).
Luso from FFTA2 and Balthier from FF12 are obtainable party members. Fast running of the trains was of a nature not seen since the pre-war. The Knight's skillset Break has changed to Ruin. At first, it was noted that the lion faced towards the rear of the tender which.
Many skills and skillsets are changed in name.
Many Character names are spelt a bit differently and the language has changed a bit (said to be more medieval w/e that means).
