Christine Daaé, Try to Forgive

When Christine Daae, Wishing enters the battlefield target player must put a Legendary Creature from his graveyard onto the battlefield.
Put a Forgiveness Token on that creature. The creature cannot attack you while it has a
Forgiveness Token.
{t}{x}: Remove a Forgiveness Token from target creature. X is equal to target creature's power.
Each creature you control gain X Toughness
until the end of the turn.