The longest nights are measured not in hours, but in heartbeats.

The List

Survive the Night

Target creature gets +1/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Shadows over Innistrad

Target creature gets +1/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)
Investigate. (Put a colorless Clue artifact token onto the battlefield with "{2}, Sacrifice this artifact: Draw a card.")