Uff, the image of going through all of this for who knows how long, until you finally get that dreamy Rainbow.
You have to what ? Make an account, go through tutorial, get 50 gems, roll, hope for luck if nothing, delete the account rinse and repeat ?

Not sure how many but on DMM those 50 FG should be almost instanteous so that helps a little bit.
Not sure I would be willing be able to do that ad infinitum until the jackpot rainbow flower pot hit me in the gacha.

Though I suppose those who are willing to go that far, and re-do over and over and over again, in a certain way, it is commendable, the tenacity.