"Somewhere in the multiverse, there is a world I call "Earth Prime". Every Earth is a variation of this one, the original - and once I destroy it, all reality will follow."
- Owlman, Justice League: Crisis on Two Earths
It seems, like branches hanging off a single tree, each of these dimensions sprang from a common source. Destroy the source, and you would set off a chain reaction that would destroy Ninja Turtles everywhere, FOREVERMORE!
- The Shredder, Turtles Forever