Tohaka is the official "sequel" of Sonic 2 Ultima. Ultima worked on Sonic 2 Ultima originally to get a feel for Sonic modifications in general, and as a kind of practice run. Once he felt that he was experienced enough, he moved on to begin this modification, whilst announcing the discontinuation of his previous modification project.
Tohaka began as a quest to show everyone a modification that looked and played just as well as the original games did. It was originally going to be named after the word "Perfect" in Japanese, due to the creator's obsession with anything Japanese. However, it was quickly discovered that using an actual Japanese name, while original, would be very confusing in presentation, and thus the name "Tohaka" was born. The word Tohaka itself does not mean anything, but through association has been commonly related to the idea of a high quality piece of work.
Currently, Ultima is reaching out in new directions with this hack, and rather than concentrating on finishing more level designs (which appear to be his forte), he seems to be exploring the more technical aspects of modification, such as adding an "Emerald Hunt" system in place of the game's special stages in the same way that the Game Gear and Master System Sonic titles worked.
In terms of level design, Tohaka has been constantly praised for its elegant and professional designs and the continuity and speed of the levels. People were especially pleased when they saw the result of a 7 month gap, in which no releases were made but lots of work went on behind the scenes. The results astonished many, and at the time some even considered it to be the best modification ever made.
