The Great Library

All of The Great Library's abilities cause it to tap for an additional 2 turns.
{3}{t}: Search any graveyard for target creature with converted mana cost 3 or less and place them onto the battlefield tapped. Exile when that creature leaves the field instead of placing into graveyard.
{6}{t}: Search any graveyard for target creature with converted mana cost 6 or less and place them onto the battlefield tapped. Exile when that creature leaves the field instead of placing into graveyard.