Here’s a great way to acquire the Ultima spell for use by Ramza. Have Ramza in the battle at Limberry Castle and make sure he’s a Squire (no other class). With some luck during the first or second battles there, Ceilia or Ledw will cast Ultima on Ramza. As long as Ramza is a Squire when this happens, he’ll learn Ultima as a Squire skill which can then be reproduced at will.