I think if you programer you can make game clan war like COC but prize for champion is GB and system like champion league in football , every grup filled by four clan
GRUP 1 GRUP2 GRUP3 GRUP4
CLAN A CLAN E CLAN I CLAN M
CLAN B CLAN F CLAN J CLAN N
CLAN C CLAN G CLAN K CLAN O
CLAN D CLAN H CLAN L CLAN P
sorry but it's just my suggestion