the Great War
thanks to Timocharis for her help on the subject
Before entering into the major upcoming conflict between the DU and the LU, it is important to tell the story of the old conflict. Thousands of years ago (about 15,000 to 20,000 earth years, according to some fragmented records) the DU and the LU were not enemies, simply two dimensions who co-existed and balanced the overall universe.
While a galaxy may seem an incredibly large place to people on Earth, there were about 500 total major galaxies each in the Dark and Light Universes, each ruled by a single empire and consisting of googles and googles (a google is a one followed by one hundred zeros) of people. This meant there was a lot of life energy and a lot of senshi.
Every so often, an Intergalactic Imperial Council would convene, and representatives from the Dark and Light empires would come to talk about issues concerning them, forge alliances, promote trade, etc. (Sort of an intergalactic UN.) Sessions of the Council would often last for months due to the large number of representatives. (Incidentally, the Council was rarely held in the same place more than once; at the end of every Council, representatives would vote for who the next host should be, and few empires could afford to host it two consecutive times.)
At one point, the Council was held in a galaxy called Clreen. Clreen was a relatively powerful DU galaxy that had an Imperial Monarchy. A major focus of the Council was the daughter of the current Emperor-King Ludbago gesl Matezik II. The other Empires were greatly interested in a marital alliance through this daughter, and the Emperor King of Clreen was expected to choose from a list of suitors at the Council. This in and of itself was nothing new; other marriage arrangements had taken place at previous Councils.
The Imperial Princess Mirkt was considered quite pretty for a humanoid, being of sound health and gentle mannerisms. Her two major suitors were Grand Lord Eyla of the DU galaxy Pililla and Sub-General Tormakin Fizwick Pesley Mainer, Prince of the LU galaxy Sisbin Horn. A week before the end of the Council, Emperor-King Ludbago gesl Matezik II announced that he had chosen Grand Lord Eyla to be his daughter’s husband. Sub-General Mainer did not agree with the Emperor-King’s decision and kidnapped Imperial Princess Mirkt, taking her back to Sisbin Horn with him.
Immediately, the Emperor-King and the Grand Lord called for the death of Sub-General Mainer. Sisbin Horn refused to accommodate the Emperor-King and the Grand Lord, protecting the Sub-General and the Imperial Princess when the two publicly announced their love for each other and desire not to be separated. Sisbin Horn’s major allies, Frimuk, Loportanussus, and Tesbettle (all LU galaxies), agreed with Sisbin Horn and declared war on Clreen and Pililla.
Here’s where the complications began. Pilalla and Clreen called to all the DU galaxies and argued that these LU galaxies were insulting the moral structure of the DU. (In the DU, after all, people are expected to forego their own desires for the betterment of everyone else.) Based upon this and other points made by the Pilallee (people of Pilalla) and the Clreen, many DU galaxies agreed to declare war. Eventually, a good majority of the DU was united under the leadership of the Dark Universalis Senshi and launched an assault on the LU galaxies.
At first, the LU galaxies splintered into small factions, some wanting to fight the DU, some wanting nothing to do with the conflict. This was the chaotic nature of the LU in play. The DU decimated empire after empire on their holy tirade, eventually forcing the Universalis Senshi into the conflict.
In order to prevent the DU from fully conquering the LU, the LU senshi (led by the Universalis Senshi) sacrificed themselves, effectively shutting down all portals and transportation. And so the Great War ended, only to be reopened in the future by a new generation of senshi.
Obviously, there's more to the story (stuff like the details of the battle, etc.) but it's not necessary to know.