Cast Clay Champion by paying six ({G} magic symbol) .
Clay Champion enters the battlefield with nine +1/+1 counters on it.
Clay Champion entering the battlefield triggering its last ability, to no effect.
Activate Drafna's first ability by paying ({1} magic symbol) ({U} magic symbol) , returning Clay Champion from the battlefield to your hand.
Clay Champion leaves the battlefield, triggering Resourceful Defense, putting all counters that were on Clay Champion on Crystalline Crawler.
Activate Crystalline Crawler's first ability eight times by removing eight +1/+1 counters from it, adding ({U} magic symbol) and seven ({G} magic symbol) .
Repeat.
Results
Infinite +1/+1 counters on permanents you control.