Being a champion takes a lot of hard work and time to put into your base. Also being a champion means being at the top rank in the game. I am proposing the idea of a round matchmaking system.
How it works: simple, once you are a champion, every base that is also a champion is able to be attacked. You can be attacked by any other champion as well.
Trophies: there could be a balanced amount of trophies gained and lost for attacking bases
Maybe you could make it 20 trophies for winning and 20 for losing. It could change depending on the trophy range possibly ex: someone with 4200 trophies attacking someone with 3300. The trophies possible go 5 for a win and 5 for a loss. But this is just an idea.
No more shields: 40 percent shields at champions league are ridiculous. This is the only way I see you can prevent cheap shields at the moment. The only "real" shield should be at one or two stars. You are a champion not an exploiter!
3200 means 3200: title says it all, you must have 3200 trophies to stay in this advanced league. Any lower and you are knocked down to masters 1.
Lastly, it will make it interesting: this update will change the high level game for all high level champions. This will cause a real competition for first place instead of trying to figure out a new way to exploit the flaws.
Thank you you for reading. Post ideas below. Critisism is good people!

