Hey and welcome to the forums!
Dear OP, please ignore any hurtful comments that were put by other users before this post, obviously they don't know that you are new to this game, but I do
Your concept for this idea is great, but think of it, if you have the gem king, here are some things the people will probably not like and some problems associated with it
# 1 - The percentage of gems stolen you choose is creative, but 20% is pretty high even though it doesn't sound that much. So lets say that I had 5,000, and I got 3 starred by a gem king. 20% of 5,000 gems comes out to a grand total of 1,000 gems stolen. I would be seriously ticked off it it were to happen to me. Many players might make rage threads like
"OMG I JUST GOT RAIDED AND THEY STOLE 1,000 GEMS, OMG SUPERCELL!!!!



"
I hope you know what I mean
#2 - If this were to be implemented, supercell would lose profits because of the gem king. Even though you said it will cost real money, in the long run it will lower their profits. Who would buy free gems when you can just steal them from people
# 3 - If the gem king were added, the trophy ranges will get unbalanced. The sub 200 will be over populated with players because of the very low lvls and the 500 gems they get at the tutorial.
After you get out of the sub 200, you will probably see 99.9% inactive people since they all left due to the possibility of free gems, the trophy range from 500 trophies to 2000 trophies will be empty. On the other hand, when you start getting into the 2200+ trophy range, it will get way more overpopulated again because many high lvl players are gemmers and they are likely to win many many gems. So in conclusion, the trophy ranges will be way to unbalanced
Overall, you concept is good, but according to the 3 reasons I stated above, this is why this plan will not work.

Because you came up with this idea, do not EVER think of yourself as a loser or take anything personalty from the messages above, when someone posts something mean, just ignore and report the issue, these personal attacks with new members are getting way to out of hand
As a new member, you have the right to share out any ideas you might want in the game, don't worry you're not the only one to begin not so well, almost every forumer including me myself when they were new didn't know much about the forums.
Please don't quit the forums if you see any of those nasty rude messages, again like I said, you have the right of a new member to share out ANY new ideas that come into mind, and people will try their best to give their output on it
Clash on!
