Doctrine of the Colossus

Doctrine (You may only have 1 doctrine in your deck. A doctrine cannot be affected by any effect other than its
own. If there are 2 doctrines on the field, exile this card.)
Choose 1 creature you control, that you summoned. Destroy all other creatures you control, then, give X 1+/0, and 0/1+ counters to the remaining creature, where X is the the combined power and toughness respectively of those creatures destroyed. It also gains indestructible. If this card leaves the field exile that creatur