An interesting choice. This means, a minor creature, such as a bloodsucker, would easily destroy a creature like that. In that case, I'd like to see if this stands up to the algorithm. Phantom Fox says that quanta cost is determined mostly by attack, which would be 9, and since it's health is over 5, it also adds 1. So, does it's ability really reduce the cost by 5? I'd say 3 tops, so, reduce the health by 2, and that brings it down to a total cost of 6. I'm not sure what the final reduction would be, but if push comes to shove, you might want to set up the unupped as 6.