Well over five billion years ago, the human race was spread all across the galaxy on different planets with different species, coexisting as a slightly more than equal part of their government and daily life. However, an accident with an experimental time machine and an unapproved test subject changed all of that. The time machine didn't go back in time. It sent everything else back in time, before life had begun on earth. But time was just barely being understood then, and it behaved in strange ways. There were several places in the galaxy that had not been sent back in time, and most of them were lost or destroyed in the ensuing chaos. For example, a city on Kelrung-6 was left behind, but the planet was in a very different part of its rotation around its star, causing everyone in the city suffocated in the vacuum of space.
One city on earth and a planet were not sent back in time the city would be known as Atlantis, named after the planet that had survived the changes of time. A few thousand years later, the city sunk into the sea and was lost, but not before being put into legends by the restarting human race. Meanwhile, on the planet of Atlantis, humans began to change. They developed a new power and flourished in technological knowledge. The power the Atlantians began to develop was strange and scientifically impossible. To put it simply, they could move water with their minds.
A few years later, after a war severely decreased the population, people began to realise that their power was inversely related to the population of the species. Not humans, but the Atlantians, because the power had changed their DNA in unique ways and created a new species. A scientist then created a theoretical equation on how many gallons an Atlantian could influence at any given population, which was yet to be disproven.
About 2 million years after the accident with the time machine, a new race, more advanced than the Atlantian, entered the galaxy with the intent of conquest. The first planet they attacked fell quickly, having no intelligent life to withstand the enemy. The second planet was Atlantis. Seven months after they landed, all but a single city had been taken over by the enemy. The Atlantians realised that they could not save their planet after the enemy first landed, and began to frantically create a light speed rocket to take the species to another planet far away from the enemy, and to restart anew.
The Atlantians called the mission 'Last Chance', and were able to make three rockets with an experimental engine capable of light speed travel, and named the rockets Resilience, Hope, and Willpower. The three main characteristics that they would need to have to restart the species. They packed the rockets with the most advanced technology they could spare, and prepared to launch them before it was too late.