User blog comment:Majesty1/Trading Units Campaign/@comment-26455864-20150902211229

Glad to see it's a blog post now. :)

Anyway, regarding the trading units, it will never become a thing because it will break the balance of the game. If you could get any unit you want from the trading system, there wouldn't be a reason to buy gems from Gumi, depriving them of money that they need to keep the game up and running.