Ultima was re-released on December 23rd, 1986 by Origin on a number of
platforms, including Apple II, IBM-PC and C64. Details were changed and
the whole game got a face-lift to make it more appealing to the players
of the mid-eighties. Origin decided to rewrite Ultima in assembly
language, change the graphics and some of the towns, names and puzzles
in the game.

The rewrite version, being written in assembly, is smaller and fits on a
single disk rather than two.