Prevent all combat damage that would be dealt this turn by creatures with no +1/+1 counters on them.
"Woodlands and laws. Both grow faster than the Azorius's ability to manage them." —Suniel the Woodwise
Official Rulings for Hindervines
1/24/2013 : Hindervines checks whether a creature has a +1/+1 counter on it at the moment it deals damage. It doesn't matter whether a creature had a +1/+1 counter, or was even on the battlefield, when Hindervines resolved.