>>527573627
It's literally random with no easy way.
I have been playing for 2 years and I never got her.
I even have her SB skin, but since I don't have her I can't use it.

The only "easy" way to get Scarlet would be reroll over and over again until you get her.
But that could take several days or even weeks.

Even with the wishlist and molds you can easily never get her at all.