Katara, Bending Prodigy (#59)

Type: Legendary Creature — Human Warrior Ally

Text: At the beginning of your end step, if Katara is tapped, put a +1/+1 counter on her.
Waterbend {6}: Draw a card. (While paying a waterbend cost, you can tap your artifacts and creatures to help. Each one pays for {1}.)

"You can't knock me down!"

Set: Avatar: The Last Airbender (#59)