The Slingshot effect was this plot element used in two Star Trek original episodes and the fourth movie of a starship going at a vast speed in space that the ship the main cast traveled on was sent into Earth's past. I've been thinking of a similar solution to Metroid Prime's conflictive beginnings. It starts perhaps a little while after Dark Samus takes over the Pirate Homeworld. With hordes of Space Pirates and their technology under her control, she begins an endeavor to preserve her existence. Discovering an ancient Space Pirate fighter on Phaaze with a Metroid Egg shell near it, Dark Samus correctly surmised that the egg her past self hatched from came from around her own time period. Studying science similar to the Slingshot Effect and acquiring an egg from SR388, she then made a move to send her egg far into the past of Phaaze around the time the Tallon IV Leviathan where it would hatch and the resulting Metroid would become the guardian of the Leviathan. Staying with it for several decades in space and on Tallon IV until it's death by Samus Aran and rebirth into Dark Samus. Thus, through a casual loop, Dark Samus ensured she existed to begin with.