2. David Mack
With no more films or episodes to constrain them, 24th Century tie-in novels took their new found free reign and ran with it. Books featured events that would never have been considered on screen, Janeway's assimilation to become a Borg Queen and subsequent death is just one, but there was one event that changed the whole galaxy forever. Written by David Mack, the Destiny trilogy spans over two centuries, from post Enterprise in 2156 to post Nemesis 2381. When the crew of the Columbia come into contact with the elusive Caeliar little do they realise how much of an impact they have had, and will have on a galactic scale. With the Borg having switched from assimilation to all out invasion, the Federation loses planet after planet to their destruction. Even a combined fleet including Starfleet, Klingon, Cardassian, and Breen ships is powerless to stop the onslaught, and total annihilation is all but inevitable. The Borg are stopped as always, but with the death toll in the billions, not without paying such a heavy price. This one event, spread out over three books, is the defining moment in post-Nemesis Star Trek fiction and sets the scene for countless novels that came after, with more than a handful specifically referring back to that one pivotal moment brought to the page by Mack.