Gem Tower

Gem Tower a structure/building where you can steal gems from your enemy after a distruction or successful raid. This Tower is guarded by a Fairy which keeps the tower sturdy, she can be killed by a poison spell.
The amount of Gems is depending on the enemy's gem owned, probably 2 to 5 percent of that. The owner will not loss Gems after the raid.
This Tower can be destroyed only by the heroes.
Can be unlocked at TH8, lower TH can destroy the Gem Tower but no gems can be collected.
During war, there will be Gem bonus after a victory to those who destroyed the Tower only.

Any suggestions/Comments are welcome!