How to unlock and at what level?

Lord_Rhygar

The thing is, if they actually do want to make more money they won't price it so ridiculously high.
In a business perspective, it's shooting yourself in the foot because you're limiting the potential buyers to your product by a lot. Better to make it attainable with 100-200$ worth of gold so that you get more customers.

fcalife

any amount of vitality can be stacked, it jjust takes more time.