Living Lore

Oracle Text

As Living Lore enters the battlefield, exile an instant or sorcery card from your graveyard.

Living Lore's power and toughness are each equal to the exiled card's converted mana cost.

Whenever Living Lore deals combat damage, you may sacrifice it. If you do, you may cast the exiled card without paying its mana cost.

Card Rulings

2/25/2015 If there are no instant or sorcery cards in your graveyard as Living Lore enters the battlefield, it will enter the battlefield as a 0/0 creature and be put into its owner’s graveyard due to having 0 toughness.
2/25/2015 If Living Lore leaves the battlefield, the ability that defines its power and toughness will lose track of the exiled card. Its power and toughness are 0 in other zones.
2/25/2015 Similarly, if the exiled card somehow leaves exile while Living Lore is on the battlefield, it will become a 0/0 creature and be put into its owner’s graveyard (unless something else is raising its toughness).
2/25/2015 Living Lore’s last ability will trigger whenever it deals combat damage, no matter if that damage is dealt to an opponent, an opposing planeswalker, or a creature it’s blocking or being blocked by. You choose whether to sacrifice Living Lore as that ability resolves.
2/25/2015 When casting a card with Living Lore’s last ability, ignore timing restrictions based on the card’s type. Other timing restrictions, such as “Cast [this spell] only during combat,” must be followed.
2/25/2015 If you cast a card “without paying its mana cost,” you can’t pay alternative costs. You can pay additional costs. If the card has mandatory additional costs, you must pay those.
2/25/2015 If you choose to cast the exiled card and it has in its mana cost, you must choose 0 as its value.