“A whole tangle and labyrinth — I’m convinced that she’s somewhere there!”
It’s the same old story. You start out with another Earth on the opposite side of the sun, where all the good people are evil, and everyone’s got a mustache except the people who are supposed to have mustaches. But you can’t leave well enough alone.
Pretty soon, you’ve got people from the other universe popping up to cause trouble. They move into your house and call themselves Cassandra, and refuse to admit that they’re the spinoff. They demand crossovers and reboots and flash-forwards, rewriting time to suit their own purposes. Before you know it, you’ve got Skaro Daleks fighting Necros Daleks, and 616-Thor taking a spare hammer from Ultimate Thor, and two completely different ways for Edith Collins to die, and anything that you do to try to fix the problem only makes everything worse.
They say that those who don’t remember the past are doomed to repeat it, but it turns out the people who do remember the past repeat it even more. It’s gonna get repeated either way.