Having duplicates from the other world could be very interesting for Flash. I have a feeling that the Killer Frost we see first won't necessarily be the Caitlyn we're used to.
I've also got theories on Cisco's inspiration for the Flash signal being something from the other world as well.
Good day from the house of the haunted
Get a job, get a house, get a coffin
Don't stray from the path, remain where you at
That maximizes our profit
Is that blunt? Oh well, hell, so's this boot
We live to hear you say "please don't shoot"
A pure delight, c'mon, make my night
When I file reports what's right's what I write