Sage of Ancient Lore
Creature — Human Shaman Werewolf
Sage of Ancient Lore's power and toughness are each equal to the number of cards in your hand.
When Sage of Ancient Lore enters the battlefield, draw a card.
At the beginning of each upkeep, if no spells were cast last turn, transform Sage of Ancient Lore.
Illustrated by
Shadows over Innistrad#225RareEnglishLegality
Rulings
If you have no cards in hand after Sage of Ancient Lore enters the battlefield, it will be put into your graveyard before its first triggered ability resolves. You’ll draw a card, but Sage of Ancient Lore will already be gone.
The abilities that transform a Werewolf back and forth look at the entire previous turn, even if the Werewolf with that ability wasn’t on the battlefield for some or all of that turn.
To trigger the Werewolf’s back face’s transform ability, a single player must have cast two or more spells during the previous turn. If multiple players each cast just one spell during the previous turn, the ability won’t trigger.
For more information on double-faced cards, see the Shadows over Innistrad mechanics article (http://magic.wizards.com/en/articles/archive/feature/shadows-over-innistrad-mechanics).